Organic light-emitting device

ABSTRACT

An organic light-emitting device includes: a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode and including an emission layer. The organic layer includes a first compound represented by Formula 1 and a second compound represented by Formula 2:

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication Nos. 10-2018-0027704, filed on Mar. 8, 2018, and10-2019-0021290, filed on Feb. 22, 2019, in the Korean IntellectualProperty Office, the disclosure of both of which are incorporated hereinin their entireties by reference.

BACKGROUND 1. Field

One or more embodiments relate to an organic light-emitting device.

2. Description of the Related Art

Organic light-emitting devices are self-emission devices that producefull-color images, and also have wide viewing angles, high contrastratios, short response times, and excellent characteristics in terms ofbrightness, driving voltage, and response speed, compared to relateddevices in the art.

An example of such organic light-emitting devices may include a firstelectrode disposed on a substrate, and a hole transport region, anemission layer, an electron transport region, and a second electrode,which are sequentially disposed on the first electrode. Holes providedfrom the first electrode may move toward the emission layer through thehole transport region, and electrons provided from the second electrodemay move toward the emission layer through the electron transportregion. Carriers, such as holes and electrons, recombine in the emissionlayer to produce excitons. These excitons transit from an excited stateto a ground state, thereby generating light.

SUMMARY

Aspects of the present disclosure are directed toward an organiclight-emitting device.

Additional aspects will be set forth in part in the description whichfollows and, in part, will be apparent from the description, or may belearned by practice of the presented embodiments.

According to an embodiment, an organic light-emitting device includes:

a first electrode;

a second electrode facing the first electrode; and

an organic layer between the first electrode and the second electrodeand including an emission layer,

wherein the organic layer further includes a first compound representedby Formula 1 and a second compound represented by Formula 2:

In Formulae 1, 1-1, 1-2, and 1-3,

CY₁ and CY₂ may each independently be a group represented by one ofFormulae 1-1, 1-2, and 1-3,

m1 and m2 may each independently be 0, 1, or 2, wherein the sum of m1and m2 is 2,

L₁ and L₂ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted divalent non-aromaticcondensed heteropolycyclic group, and —Si(Q₁)(Q₂)-,

b1 may be an integer of 0 to 5,

b2 may be an integer of 0 to 5,

X₁ to X₄ may each independently be selected from a single bond, *—O—*,*—S—*, *—C(R₈)(R₉)—*′, *—C(═O)—*′, *—B(R₈)(R₉)—*′, *—N(R₈)—*′,*—P(R₈)—*′, and *—Si(R₈)(R₉)—*′,

rings A₁ to A₆ may each independently be a C₅-C₆₀ carbocyclic group or aC₂-C₆₀ heterocyclic group,

R₁ to R₉ may each independently be selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, anamino group, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═O)(Q₁),—S(═O)(Q₁), —S(═O)₂(Q₁), —P(═O)(Q₁)(Q₂), and —P(═S)(Q₁)(Q₂),

a1 to a7 may each independently be an integer from 1 to 8, and

wherein, in Formula 2,

M₁₁ may be selected from platinum (Pt), palladium (Pd), copper (Cu),silver (Ag), gold (Au), rhodium (Rh), iridium (Ir), ruthenium (Ru),osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu),terbium (Tb), and thulium (Tm),

A₁₁ to A₁₄ may each independently be selected from a C₅-C₆₀ carbocyclicgroup and a C₁-C₆₀ heterocyclic group,

Y₁₁ to Y₁₄ may each independently be nitrogen (N) or carbon (C),

T₁₁ to T₁₄ may each independently be selected from a single bond, oxygen(O), and sulfur (S),

L₁₁ to L₁₃ may each independently be selected from a single bond,*—O—*′, *—S—*′, *—C(R₁₅)(R₁₆)—*′, *—C(R₁₅)═*′, *═C(R₁₅)—*′,*—C(R₁₅)═C(R₁₆)—*′, *—C(═O)—*′, *—C(═S)—*′, *—C═C—*′, *—B(R₁₅)—*′,*—N(R₁₅)—*′, *—P(R₁₅)—*, *—Si(R₁₅)(R₁₆)—*′, *—P(═O)(R₁₅)(R₁₆)—*′, and*—Ge(R₁₅)(R₁₆)—*′,

b11 to b13 may each independently be an integer from 0 to 3,

when b11 is 0, A₁₁ and A₁₂ may not be linked to each other, when b12 is0, A₁₂ and A₁₃ may not be linked to each other, and when b13 is 0, A₁₃and A₁₄ may not be linked to each other,

L₁₄ to L₁₆ may each independently be selected from *—O—*′, *—S—*′,*—C(═O)—*′, *—C(═S)—*′, *—B(R₁₇)—*′, *—N(R₁₇)—*′, *—P(R₁₇)—*′,*—Si(R₁₇)(R₁₈)—*′, *—P(═O)(R₁₇)(R₁₈)—*, *—Ge(R₁₇)(R₁₈)—*′, a divalentC₂-C₂₀ hydrocarbon group, a divalent C₅-C₆₀ carbocyclic group, and adivalent C₁-C₆₀ heterocyclic group,

b14 and b15 may each independently be an integer from 1 to 5,

b16 may be an integer from 0 to 5,

when b16 is 0, L₁₆ may be a single bond,

R₁₁ to R₁₈ may each independently be selected from hydrogen, deuterium,—F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, anamidino group, a hydrazino group, a hydrazono group, a substituted orunsubstituted C₁-C₆₀ alkyl group, a substituted or unsubstituted C₂-C₆₀alkenyl group, a substituted or unsubstituted C₂-C₆₀ alkynyl group, asubstituted or unsubstituted C₁-C₆₀ alkoxy group, a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedC₁-C₆₀ heteroaryloxy group, a substituted or unsubstituted C₁-C₆₀heteroarylthio group, a substituted or unsubstituted monovalentnon-aromatic condensed polycyclic group, a substituted or unsubstitutedmonovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═O)(Q₁),—S(═O)(Q₁), —S(═O)₂(Q₁), —P(═O)(Q₁)(Q₂), and —P(═S)(Q₁)(Q₂),

R₁₅ and R₁₁; R₁₅ and R₁₂; R₁₅ and R₁₃; or R₁₅ and R₁₄ may optionally belinked to form a substituted or unsubstituted C₅-C₆₀ carbocyclic groupor a substituted or unsubstituted C₁-C₆₀ heterocyclic group,

a11 to a14 may each independently be an integer from 1 to 8,

* and *′ each indicate a binding site to a neighboring atom,

at least one substituent of the substituted C₃-C₁₀ cycloalkylene group,the substituted C₁-C₁₀ heterocycloalkylene group, the substituted C₃-C₁₀cycloalkenylene group, the substituted C₁-C₁₀ heterocycloalkenylenegroup, the substituted C₆-C₆₀ arylene group, the substituted C₁-C₆₀heteroarylene group, the substituted divalent non-aromatic condensedpolycyclic group, the substituted divalent non-aromatic condensedheteropolycyclic group, the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group may be selected from:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group (wherein a carbazolylgroup in the monovalent non-aromatic condensed heteropolycyclic group isexcluded), —Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁),—S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂); and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may each independentlybe selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group,a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkylgroup, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ arylgroup substituted with a C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl groupsubstituted with a C₆-C₆₀ aryl group, a terphenyl group, a C₁-C₆₀heteroaryl group, a C₁-C₆₀ heteroaryl group substituted with a C₁-C₆₀alkyl group, a C₁-C₆₀ heteroaryl group substituted with a C₆-C₆₀ arylgroup, a monovalent non-aromatic condensed polycyclic group, and amonovalent non-aromatic condensed heteropolycyclic group.

According to another embodiment, a flat-panel display apparatusincludes: a thin film transistor including a source electrode, a drainelectrode, and an active layer; and the organic light-emitting devicedescribed above, wherein the first electrode of the organiclight-emitting device is electrically connected to one of the sourceelectrode and the drain electrode of the thin film transistor.

BRIEF DESCRIPTION OF THE DRAWING

These and/or other aspects will become apparent and more readilyappreciated from the following description of the embodiments, taken inconjunction with the drawing, which is a schematic view of an organiclight-emitting device according to an embodiment.

DETAILED DESCRIPTION

Reference will now be made in more detail to embodiments, examples ofwhich are illustrated in the accompanying drawing, wherein likereference numerals refer to like elements throughout. In this regard,the present embodiments may have different forms and should not beconstrued as being limited to the descriptions set forth herein.Accordingly, the embodiments are merely described below, by referring tothe drawing, to explain aspects of the present description. As usedherein, the term “and/or” includes any and all combinations of one ormore of the associated listed items. Expressions such as “at least oneof,” when preceding a list of elements, modify the entire list ofelements and do not modify the individual elements of the list.

Throughout the description, the term “ring” and “group” areintercheagably used in describing cyclic functional groups. For example,“a pyrene ring” is used to refer to a pyrene group, and vice versa.Also, any numerical range recited herein is intended to include allsub-ranges of the same numerical precision subsumed within the recitedrange. For example, a range of “1.0 to 10.0” is intended to include allsubranges between (and including) the recited minimum value of 1.0 andthe recited maximum value of 10.0, that is, having a minimum value equalto or greater than 1.0 and a maximum value equal to or less than 10.0,such as, for example, 2.4 to 7.6. Any maximum numerical limitationrecited herein is intended to include all lower numerical limitationssubsumed therein and any minimum numerical limitation recited in thisspecification is intended to include all higher numerical limitationssubsumed therein. Accordingly, Applicant reserves the right to amendthis specification, including the claims, to expressly recite anysub-range subsumed within the ranges expressly recited herein.

An organic light-emitting device according to an embodiment may include:a first electrode; a second electrode facing the first electrode; and anorganic layer between the first electrode and the second electrode andincluding an emission layer,

wherein the organic layer may further include a first compoundrepresented by Formula 1 and a second compound represented by Formula 2.

The first compound may be represented by Formula 1:

In Formulae 1, 1-1, 1-2, and 1-3, CY₁ and CY₂ may each independently bea group represented by one of Formulae 1-1, 1-2, and 1-3.

m1 and m2 may each independently be 0, 1, or 2, wherein the sum of m1and m2 is 2. For example, m1 and m2 may each be 1; m1 may be 2 and m2may be 0; or m1 may be 0 and m2 may be 2.

In Formulae 1, 1-1, 1-2, and 1-3, L₁ and L₂ may each independently beselected from a substituted or unsubstituted C₃-C₁₀ cycloalkylene group,a substituted or unsubstituted C₁-C₁₀ heterocycloalkylene group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenylene group, a substitutedor unsubstituted C₁-C₁₀ heterocycloalkenylene group, a substituted orunsubstituted C₆-C₆₀ arylene group, a substituted or unsubstitutedC₁-C₆₀ heteroarylene group, a substituted or unsubstituted divalentnon-aromatic condensed polycyclic group, a substituted or unsubstituteddivalent non-aromatic condensed heteropolycyclic group, and—Si(Q₁)(Q₂)-.

In one embodiment, L₁ and L₂ may each independently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-fluorenylene group, a benzofluorene group, a dibenzofluorenegroup, a phenanthrenylene group, an anthracenylene group, a pyrenylenegroup, a chrysenylene group, a pyridinylene group, a pyrazinylene group,a pyrimidinylene group, a pyridazinylene group, a quinolinylene group,an isoquinolinylene group, a quinoxalinylene group, a quinazolinylenegroup, a pyrazolylene group, an imidazolylene group, an oxazolylenegroup, an isoxazolylene group, a thiazolylene group, an isothiazolylenegroup, an oxadiazolylene group, a thiadiazolylene group, adithiazolylene group, a carbazolylene group, and a triazinylene group;

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-fluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a pyrenylene group, a chrysenylene group, a pyridinylene group, apyrazinylene group, a pyrimidinylene group, a pyridazinylene group, aquinolinylene group, an isoquinolinylene group, a quinoxalinylene group,a quinazolinylene group, a carbazolylene group, and a triazinylenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an isoindolyl group, a quinolinyl group, an isoquinolinyl group,a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and atriazinyl group; and

—Si(Q₄)(Q₅)-, and

Q₄ and Q₅ may each independently be selected from:

a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, and a phenyl group; and

a phenyl group, a biphenyl group, a terphenyl group, and a naphthylgroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group.

For example, L₁ may be selected from:

a phenylene group, a pyridinylene group, and a pyrazolylene group;

a phenylene group, a pyridinylene group, and a pyrazolylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group; and

—Si(Q₄)(Q₅)-, and

Q₄ and Q₅ may each independently be selected from:

a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, and a phenyl group; and

a phenyl group, a biphenyl group, a terphenyl group, and a naphthylgroup, each substituted with a C₁-C₁₀ alkyl group.

In Formulae 1, 1-1, 1-2, and 1-3, b1 and b2 may each independently be aninteger from 0 to 5. For example, b1 and b2 may each independently be 0,1, 2, or 3.

In Formulae 1-1, 1-2, and 1-3, X₁ to X₄ may each independently beselected from a single bond, *—O—*, *—S—*, *—C(R₈)(R₉)—*′, *—C(═O)—*′,*—B(R₈)(R₉)—*′, *—N(R₈)—*′, *—P(R₈)—*′, and *—Si(R₈)(R₉)—*′.

In Formulae 1-1, 1-2, and 1-3, A₁ to A₆ may each independently be aC₅-C₆₀ carbocyclic group or a C₂-C₆₀ heterocyclic group.

In one embodiment, A₁ to A₆ may each independently be selected from abenzene ring, a naphthalene ring, a pyridine ring, a pyrimidine ring, apyrazine ring, a pyridazine ring, a triazine ring, a quinoline ring, anisoquinoline ring, a quinoxaline ring, a quinazoline ring, and a ringrepresented by Formula 4:

In Formula 4,

X₅ and X₆ may each independently be selected from *—O—*, *—S—*,*—C(R₈)(R₉)—*′, *—C(═O)—*′, *—B(R₈)(R₉)—*′, *—N(R₈)—*′, *—P(R₈)—*′, and*—Si(R₈)(R₉)—*′, and

R₈ and R₉ are the same as described in connection with R₈ and R₉ inFormulae 1-1 to 1-3.

For example, A₁ to A₅ may each independently be selected from a benzenering, a naphthalene ring, a pyridine ring, a pyrimidine ring, a pyrazinering, a pyridazine ring, and a triazine ring, and

A₆ may be selected from a benzene ring, a pyridine ring, and a ringrepresented by Formula 4-1:

In Formula 4-1,

X₆ may be *—O—* or *—S—*,

R₈ and R₉ may respectively be defined the same as R₈ and R₉ in Formulae1-1 to 1-3.

In Formulae 1-1, 1-2, and 1-3, R₁ to R₉ may each independently beselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amino group, an amidino group, ahydrazine group, a hydrazone group, a carboxylic acid group or a saltthereof, a sulfonic acid group or a salt thereof, a phosphoric acidgroup or a salt thereof, a substituted or unsubstituted C₁-C₆₀ alkylgroup, a substituted or unsubstituted C₂-C₆₀ alkenyl group, asubstituted or unsubstituted C₂-C₆₀ alkynyl group, a substituted orunsubstituted C₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂),—N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═O)(Q₁), —S(═O)(Q₁), —S(═O)₂(Q₁),—P(═O)(Q₁)(Q₂), and —P(═S)(Q₁)(Q₂).

In one embodiment, R₁ to R₉ may each independently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid group or a salt thereof, a sulfonicacid group or a salt thereof, a phosphoric acid group or a salt thereof,a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, a phenyl group, a naphthyl group, a fluorenylgroup, a pyrenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrazolyl group, an imidazolyl group, a benzimidazolyl group, apyridinyl group, a pyrimidyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a carbazolyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group;

a phenyl group, a naphthyl group, a fluorenyl group, a pyrenyl group, aphenalenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrazolyl group, animidazolyl group, a benzimidazolyl group, a pyridinyl group, a pyrimidylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a naphthyridinyl group, a quinoxalinyl group, a quinazolinylgroup, a carbazolyl group, a phenanthridinyl group, an acridinyl group,a phenanthrolinyl group, a phenazinyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, and aterphenyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, a methyl group, an ethyl group, a propyl group, an isobutylgroup, a sec-butyl group, ter-butyl group, pentyl group, an isoamylgroup, a hexyl group, a C₁-C₆₀ alkoxy group, a cyclopentyl group, acyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a naphthyl group, a fluorenyl group,a pyrenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrazolyl group, an imidazolyl group, a benzimidazolyl group, apyridinyl group, a pyrimidyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a carbazolyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group; and

—Si(Q₄)(Q₅)(Q₆) and —P(═O)(Q₄)(Q₅), and

Q₄ to Q₀₆ may each independently be selected from:

a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, and a phenyl group; and

a phenyl group, a biphenyl group, a terphenyl group, and a naphthylgroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group.

For example, R₁ to R₉ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, —Si(Q₄)(Q₅)(Q₆), and —P(═O)(Q₄)(Q₅),and

Q₄ to Q₆ may each independently be selected from:

a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, and a phenyl group; and

a phenyl group substituted with a C₁-C₁₀ alkyl group, a biphenyl group,a terphenyl group, and a naphthyl group.

In one embodiment, the first compound may a compound represented by oneselected from Formulae 1A, 1B, and 1C:

In Formulae 1A, 1B, and 1C,

X₁ to X₄, A₁ to A₆, L₁, L₂, b2, R₁ to R₇ and a1 to a7 are the same asdescribed herein in association with Formulae 1-1 to 1-3,

X₃₁ and X₃₂ are each independently the same as described in connectionwith X₃ in Formulae 1-1 to 1-3,

A₃₁ and A₃₂ are each independently the same as described in connectionwith A₃ in Formulae 1-1 to 1-3,

A₄₁ and A₄₂ are each independently the same as described in connectionwith A₄ in Formulae 1-1 to 1-3,

R₃₁ and R₃₂ are each independently the same as described in connectionwith R₃ in Formulae 1-1 to 1-3,

R₄₁ and R₄₂ are each independently the same as described in connectionwith R₄ in Formulae 1-1 to 1-3,

a31 and a32 are each independently the same as described in connectionwith a3 in Formulae 1-1 to 1-3, and

a41 and a42 are each independently the same as described in connectionwith a4 in Formulae 1-1 to 1-3.

In one embodiment, the first compound may be one selected from CompoundsBH1 to BH28:

Because the first compound represented by Formula 1 includes acarbazole, dibenzofuran, dibenzothiophene, or fluorene structure, energyis easily transferred to the second compound that is a dopant having afour-coordinate metal complex compound with high T1 energy, and a devicemay be configured so that the balance of electron and hole injection iswell maintained, thereby increasing the lifespan and efficiency thereof.

The second compound may be represented by Formula 2:

In Formula 2, M₁₁ may be selected from platinum (Pt), palladium (Pd),copper (Cu), silver (Ag), gold (Au), rhodium (Rh), iridium (Ir),ruthenium (Ru), osmium (Os), titanium (Ti), zirconium (Zr), hafnium(Hf), europium (Eu), terbium (Tb), and thulium (Tm).

In one embodiment, in Formula 2, M₁₁ may be selected from Pt, Pd, Cu,Ag, and Au.

For example, in Formula 2, M₁₁ may be Pt, but embodiments of the presentdisclosure are not limited thereto.

In Formula 2, A₁₁ to A₁₄ may each independently be selected from aC₅-C₆₀ carbocyclic group, and a C₁-C₆₀ heterocyclic group.

In one embodiment, A₁₁ to A₁₄ may each independently be selected from abenzene ring, a naphthalene ring, an anthracene ring, a phenanthrenering, a triphenylene ring, a pyrene ring, a chrysene ring, acyclopentadiene ring, a 1,2,3,4-tetrahydronaphthalene ring, a furanring, a thiophene ring, a silole ring, an indene ring, a fluorene ring,an indole ring, a carbazole ring, a benzofuran ring, a dibenzofuranring, a benzothiophene ring, a dibenzothiophene ring, a benzosilolering, a dibenzosilole ring, an indeno pyridine ring, an indolopyridinering, a benzofuropyridine ring, a benzothienopyridine ring, abenzosilolopyridine ring, an indenopyrimidine ring, an indolopyrimidinering, a benzofuropyrimidine ring, a benzothienopyrimidine ring, abenzosilolopyrimidine ring, a dihydropyridine ring, a pyridine ring, apyrimidine ring, a pyrazine ring, a pyridazine ring, a triazine ring, aquinoline ring, an isoquinoline ring, a quinoxaline ring, a quinazolinering, a phenanthroline ring, a pyrrole ring, a pyrazole ring, animidazole ring, a 2,3-dihydroimidazole ring, a triazole ring, a2,3-dihydrotriazole ring, an oxazole ring, an isoxazole ring, a thiazolering, an isothiazole ring, an oxadiazole ring, a thiadiazole ring, abenzopyrazole ring, a benzimidazole ring, a 2,3-dihydrobenzimidazolering, an imidazopyridine ring, a 2,3-dihydroimidazopyridine ring, animidazopyrimidine ring, a 2,3-dihydroimidazopyrimidine ring, animidazopyrazine ring, a 2,3-dihydroimidazopyrazine ring, a benzoxazolering, a benzothiazole ring, a benzoxadiazole ring, a benzothiadiazolering, a 5,6,7,8-tetrahydroisoquinoline ring, and a5,6,7,8-tetrahydroquinoline group ring.

In one or more embodiments, A₁₁ to A₁₄ may each independently berepresented by one selected from Formulae 2-1 to 2-43:

In Formulae 2-1 to 2-43,

X₂₁ to X₂₃ may each independently be selected from C(R₂₄) and C—*,wherein at least two of X₂₁ to X₂₃ is C—*,

X₂₄ may be N—*, and X₂₅ and X₂₆ may each independently be selected fromC(R₂₄) and C—*, wherein at least one of X₂₅ and X₂₆ is C—*,

X₂₇ and X₂₈ may each independently be selected from N, N(R₂₅), and N—*,wherein X₂₉ is selected from C(R₂₄) and C—*, provided that i) at leastone of X₂₇ and X₂₈ is N—* and X₂₉ is C—*, or ii) X₂₇ and X₂₈ are eachN—* and X₂₉ is C(R₂₄),

R₂₁ to R₂₅ are each independently the same as described in connectionwith R₁₁ in Formula 1,

b21 may be selected from 1, 2, and 3,

b22 may be selected from 1, 2, 3, 4, and 5,

b23 may be selected from 1, 2, 3, and 4,

b24 may be selected from 1 and 2, and

* indicates a binding site to a neighboring atom. For example, C—*represents a carbon atom in the ring structures of A₁₁ to A₁₄(represented by Formulae 2-1 to 2-43) that is bond to a neighboring atomincluded in a respective one of L₁₁ to L₁₅.

For example, A₁₁ and A₁₄ in Formula 2 may each independently be selectedfrom a pyrrole group, a pyrazole group, an imidazole group, a2,3-dihydroimidazole group, a triazole group, and a 2,3-dihydrotriazolegroup, but embodiments of the present disclosure are not limitedthereto.

In Formula 2, Y₁₁ to Y₁₄ may each independently be N or C.

In one embodiment, in Formula 2,

Y₁₁, Y₁₂, and Y₁₃ may each be C, and Y₁₄ may be N;

Y₁₁, Y₁₂, and Y₁₄ may each be C, and Y₁₃ may be N;

Y₁₁, Y₁₃, and Y₁₄ may each be C, and Y₁₂ may be N;

Y₁₂, Y₁₃, and Y₁₄ may each be C, and Y₁₁ may be N;

Y₁₁ and Y₁₄ may each be C, and Y₁₂ and Y₁₃ may each be N;

Y₁₁ and Y₁₄ may each be N, and Y₁₂ and Y₁₃ may each be C;

Y₁₁ and Y₁₂ may each be C, and Y₁₃ and Y₁₄ may each be N;

Y₁₁ and Y₁₂ may each be N, and Y₁₃ and Y₁₄ may each be C;

Y₁₁ and Y₁₃ may each be C, and Y₁₂ and Y₁₄ may each be N; or

Y₁₁ and Y₁₃ may each be N, and Y₁₂ and Y₁₄ may each be C.

T₁₁ to T₁₄ in Formula 2 may each independently be selected from a singlebond, O, and S.

In one embodiment, in Formula 2,

each of T₁₁ to T₁₄ may be a single bond;

T₁₁ may be selected from O and S, and T₁₂ to T₁₄ may each be a singlebond;

T₁₂ may be selected from O and S, and T₁₁, T₁₃, and T₁₄ may each be asingle bond;

T₁₃ may be selected from O and S, and T₁₁, T₁₂, and T₁₄ may each be asingle bond; or

T₁₄ may be selected from O and S, and T₁₁, T₁₂, and T₁₃ may each be asingle bond.

L₁₁ to L₁₃ in Formula 2 may each independently be selected from a singlebond, *—O—*′, *—S—*′, *—C(R₁₇)(R₁₈)—*′, *—C(R₁₇)═*′, *═C(R₁₇)—*′,*—C(R₁₇)═C(R₁₈)—*′, *—C(═O)—*′, *—C(═S)—*′, *—C≡C—*′, *—B(R₁₇)—*′,*—N(R₁₇)—*′, *—P(R₁₇)—*′, *—Si(R₁₇)(R₁₈)—*′, *—P(═O)(R₁₇)(R₁₈)—*′, and*—Ge(R₁₇)(R₁₈)—*′.

In one embodiment, L₁₁ to L₁₃ may each independently be selected from asingle bond, *—O—*′, *—S—*′, *—C(R₁₇)(R₁₈)—*′, *—C(R₁₇)═*′, *═C(R₁₇)—*′,*—B(R₁₇)—*′, *—N(R₁₇)—*′, *—Si(R₁₇)(R₁₈)—*′, and *—P(═O)(R₁₇)(R₁₈)—*′.

In one or more embodiments, L₁₁ may be *—N(R₁₇)—*′, *—C(R₁₇)(R₁₈)—*′, or*—Si(R₁₇)(R₁₈)—*′, and R₁₇ and R₁₁ may be linked to form a substitutedor unsubstituted C₁-C₆₀ heterocyclic group,

L₁₁ may be *—N(R₁₇)—*′, *—C(R₁₇)(R₁₈)—*′, or *—Si(R₁₇)(R₁₈)—*′, and R₁₇and R₁₂ may be linked to form a substituted or unsubstituted C₁-C₆₀heterocyclic group, or

L₁₂ may be *—N(R₁₇)—*′, *—C(R₁₇)(R₁₈)—*′, or *—Si(R₁₇)(R₁₈)—*′, and R₁₇and R₁₃ may be linked to form a substituted or unsubstituted C₁-C₆₀heterocyclic group.

In Formula 2, b11 to b13 may each independently be an integer from 0 to3,

when b11 is 0, A₁₁ and A₁₂ may not be linked to each other, when b12 is0, A₁₂ and A₁₃ may not be linked to each other, and when b13 is 0, A₁₃and A₁₄ may not be linked to each other.

In one embodiment, b11, b12, and b13 may each independently be selectedfrom 1, 2, and 3;

b11 may be 0, and b12 and b13 may each independently be selected from 0,1, 2, and 3;

b12 may be 0, and b11 and b13 may each independently be selected from 0,1, 2, and 3; or

b13 may be 0, and b11 and b12 may each independently be selected from 0,1, 2, and 3.

In one or more embodiments, b11, b12, and b13 may each be 1;

b11 may be 0, and b12 and b13 may each independently be 0 or 1;

b12 may be 0, and b11 and b13 may each independently be 0 or 1; or

b13 may be 0, and b11 and b12 may each independently be 0 or 1.

For example, b11 may be 1, b12 may be 1, and b13 may be 1, butembodiments of the present disclosure are not limited thereto.

In Formula 2, L₁₄ to L₁₆ may each independently be selected from *—O—*′,*—S—*′, *—C(═O)—*′, *—C(═S)—*′, *—B(R₁₉)—*′, *—N(R₁₉)—*′, *—P(R₁₉)—*′,*—Si(R₁₉)(R₂₀)—*′, *—P(R₁₉)(R₂₀)—*′, *—Ge(R₁₉)(R₂₀)—*′, a divalentC₂-C₂₀ hydrocarbon group, a divalent C₅-C₆₀ carbocyclic group, and adivalent C₁-C₆₀ heterocyclic group, and

b14 and b15 may each independently be an integer from 1 to 5, and b16may be an integer from 0 to 5, wherein, when b16 is 0, L₁₆ may be asingle bond.

In one embodiment, L₁₄ and L₁₅ may each independently be selected from*—O—*′, *—S—*′, *—C(═O)—*′, *—C(═S)—*′, *—B(R₁₉)—*′, *—N(R₁₉)—*′,*—P(R₁₉)—*′, *—Si(R₁₉)(R₂₀)—*′, *—P(R₁₉)(R₂₀)—*′, *—Ge(R₁₉)(R₂₀)—*′, anda divalent C₂-C₂₀ hydrocarbon, and

L₁₆ may be selected from a divalent C₅-C₆₀ carbocyclic group and adivalent C₁-C₆₀ heterocyclic group.

In one or more embodiments, L₁₄ and L₁₅ may each independently beselected from *—O—*′, *—S—*′, *—N(R₁₉)—*′, a C₂-C₂₀ alkylene group, aC₂-C₂₀ alkenylene group, and a C₂-C₂₀ alkynylene group,

R₁₉ may be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, apyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group,a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, anisoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, acarbazolyl group, and a triazinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, apyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group,a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, anisoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, acarbazolyl group, and a triazinyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, an amino group, an amidino group, a hydrazinegroup, a hydrazone group, a carboxylic acid group or a salt thereof, asulfonic acid group or a salt thereof, a phosphoric acid group or a saltthereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, abiphenyl group, a terphenyl group, a naphthyl group, an azulenyl group,a fluorenyl group, a spiro-fluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, apyrenyl group, a chrysenyl group, a pyridinyl group, a pyrazinyl group,a pyrimidinyl group, a pyridazinyl group, a quinolinyl group, anisoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, acarbazolyl group, and a triazinyl group,

L₁₆ may be selected from a phenylene group, a naphthylene group, afluorenylene group, a spiro-fluorenylene group, a benzofluorene group, adibenzofluorene group, a phenanthrenylene group, an anthracenylenegroup, a pyrenylene group, a chrysenylene group, a pyridinylene group, apyrazinylene group, a pyrimidinylene group, a pyridazinylene group, aquinolinylene group, an isoquinolinylene group, a quinoxalinylene group,a quinazolinylene group, a carbazolylene group, and a triazinylenegroup; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-fluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a pyrenylene group, a chrysenylene group, a pyridinylene group, apyrazinylene group, a pyrimidinylene group, a pyridazinylene group, aquinolinylene group, an isoquinolinylene group, a quinoxalinylene group,a quinazolinylene group, a carbazolylene group, and a triazinylenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an isoindolyl group, a quinolinyl group, an isoquinolinyl group,a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and atriazinyl group

For example, in Formula 2, a moiety represented by*-(L₁₄)_(b14)-(L₁₆)_(b16)-(L₁₅)_(b15) may be represented by one selectedfrom Formulae 3-1 to 3-7:

In Formulae 3-1 to 3-7, * and *′ each indicate a binding site to aneighboring atom.

In Formula 2, R₁₁ to R₂₀ may each independently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted C₁-C₆₀ heteroaryloxy group, a substituted or unsubstitutedC₁-C₆₀ heteroarylthio group, a substituted or unsubstituted monovalentnon-aromatic condensed polycyclic group, a substituted or unsubstitutedmonovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═O)(Q₁),—S(═O)(Q₁), —S(═O)₂(Q₁), —P(═O)(Q₁)(Q₂), and —P(═S)(Q₁)(Q₂),

R₁₇ and R₁₁; R₁₇ and R₁₂; R₁₇ and R₁₃; or R₁₇ and R₁₄ may optionally belinked to form a substituted or unsubstituted C₅-C₆₀ carbocyclic groupor a substituted or unsubstituted C₁-C₆₀ heterocyclic group,

a11 to a14 may each independently be an integer from 1 to 8.

In Formula 2, * and *′ each indicate a binding site to a neighboringatom.

In one embodiment, R₁₁ to R₂₀ may each independently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a cyano group, a C₁-C₂₀ alkylgroup, and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from —F, —Cl, —Br, —I, a cyano group, a phenyl group,and a biphenyl group;

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a pentalenyl group, an indenyl group, anaphthyl group, an azulenyl group, an indacenyl group, an acenaphthylgroup, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenylgroup, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a perylenyl group, apentacenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group,a silolyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an indolyl group, an isoindolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, an isoquinolinyl group, a phthalazinyl group, anaphthyridinyl group, a quinoxalinyl group, a benzoquinoxalinyl group, aquinazolinyl group, a benzoquinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, a benzofuranyl group, abenzothiophenyl group, a benzosilolyl group, a benzothiazolyl group, abenzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group,a triazolyl group, a tetrazolyl group, a thiadiazolyl group, anoxadiazolyl group, a triazinyl group, a carbazolyl group, adibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group,a benzocarbazolyl group, a naphtho benzofuranyl group, a naphthobenzothiophenyl group, a naphthobenzosilolyl group, a dibenzocarbazolylgroup, a dinaphthofuranyl group, a dinaphtho thiophenyl group, adinaphtho silolyl group, an imidazopyridinyl group, animidazopyrimidinyl group, an oxazolopyridinyl group, a thiazolopyridinylgroup, a benzonaphthyridinyl group, an azafluorenyl group, anazaspiro-bifluorenyl group, an azacarbazolyl group, an azadibenzofuranylgroup, an azadibenzothiophenyl group, an azadibenzosilolyl group, anindeno pyrrolyl group, an indolopyrrolyl group, an indeno carbazolylgroup, and an indolocarbazolyl group;

a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a pentalenyl group, an indenyl group, anaphthyl group, an azulenyl group, an indacenyl group, an acenaphthylgroup, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenylgroup, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenylgroup, an anthracenyl group, a fluoranthenyl group, a triphenylenylgroup, a pyrenyl group, a chrysenyl group, a perylenyl group, apentacenyl group, a pyrrolyl group, a thiophenyl group, a furanyl group,a silolyl group, an imidazolyl group, a pyrazolyl group, a thiazolylgroup, an isothiazolyl group, an oxazolyl group, an isoxazolyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an indolyl group, an isoindolyl group, an indazolyl group, apurinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, an isoquinolinyl group, a phthalazinyl group, anaphthyridinyl group, a quinoxalinyl group, a benzoquinoxalinyl group, aquinazolinyl group, a benzoquinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, a benzofuranyl group, abenzothiophenyl group, a benzosilolyl group, a benzothiazolyl group, abenzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group,a triazolyl group, a tetrazolyl group, a thiadiazolyl group, anoxadiazolyl group, a triazinyl group, a carbazolyl group, adibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group,a benzocarbazolyl group, a naphtho benzofuranyl group, a naphthobenzothiophenyl group, a naphthobenzosilolyl group, a dibenzocarbazolylgroup, a dinaphthofuranyl group, a dinaphtho thiophenyl group, adinaphtho silolyl group, an imidazopyridinyl group, animidazopyrimidinyl group, an oxazolopyridinyl group, a thiazolopyridinylgroup, a benzonaphthyridinyl group, an azafluorenyl group, anazaspiro-bifluorenyl group, an azacarbazolyl group, an azadibenzofuranylgroup, an azadibenzothiophenyl group, an azadibenzosilolyl group, anindeno pyrrolyl group, an indolopyrrolyl group, an indeno carbazolylgroup, and an indolocarbazolyl group, each substituted with at least oneselected from deuterium, —F, —Cl, —Br, —I, a cyano group, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexyl group, acycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenylgroup, a biphenyl group, a terphenyl group, a pentalenyl group, anindenyl group, a naphthyl group, an azulenyl group, an indacenyl group,an acenaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, aphenanthrenyl group, an anthracenyl group, a fluoranthenyl group, atriphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenylgroup, a pentacenyl group, a pyrrolyl group, a thiophenyl group, afuranyl group, a silolyl group, an imidazolyl group, a pyrazolyl group,a thiazolyl group, an isothiazolyl group, an oxazolyl group, anisoxazolyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an indolyl group, an isoindolyl group, anindazolyl group, a purinyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, an isoquinolinyl group, a phthalazinylgroup, a naphthyridinyl group, a quinoxalinyl group, a benzoquinoxalinylgroup, a quinazolinyl group, a benzoquinazolinyl group, a cinnolinylgroup, a phenanthridinyl group, an acridinyl group, a phenanthrolinylgroup, a phenazinyl group, a benzimidazolyl group, a benzofuranyl group,a benzothiophenyl group, a benzosilolyl group, a benzothiazolyl group, abenzoisothiazolyl group, a benzoxazolyl group, a benzoisoxazolyl group,a triazolyl group, a tetrazolyl group, a thiadiazolyl group, anoxadiazolyl group, a triazinyl group, a carbazolyl group, adibenzofuranyl group, a dibenzothiophenyl group, a dibenzosilolyl group,a benzocarbazolyl group, a naphtho benzofuranyl group, a naphthobenzothiophenyl group, a naphthobenzosilolyl group, a dibenzocarbazolylgroup, a dinaphthofuranyl group, a dinaphtho thiophenyl group, adinaphtho silolyl group, an imidazopyridinyl group, animidazopyrimidinyl group, an oxazolopyridinyl group, a thiazolopyridinylgroup, a benzonaphthyridinyl group, an azafluorenyl group, anazaspiro-bifluorenyl group, an azacarbazolyl group, an azadibenzofuranylgroup, an azadibenzothiophenyl group, an azadibenzosilolyl group, anindeno pyrrolyl group, an indolopyrrolyl group, an indeno carbazolylgroup, an indolocarbazolyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)(Q₃₁), —S(═O)₂(Q₃₁), —P(═O)(Q₃₁)(Q₃₂),and —P(═S)(Q₃₁)(Q₃₂); and

—Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═O)(Q₁),—S(═O)(Q₁), —S(═O)₂(Q₁), —P(═O)(Q₁)(Q₂), and —P(═S)(Q₁)(Q₂), and

Q₁ to Q₃ and Q₃₁ to Q₃₃ may each independently be selected fromhydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, aC₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a C₁-C₆₀ heteroaryloxygroup, a C₁-C₆₀ heteroarylthio group, a monovalent non-aromaticcondensed polycyclic group, a monovalent non-aromatic condensedheteropolycyclic group, a C₁-C₆₀ alkyl group substituted with at leastone selected from deuterium, —F, and a cyano group, a C₆-C₆₀ aryl groupsubstituted with at least one selected from deuterium, —F, and a cyanogroup, a biphenyl group, and a terphenyl group.

For example, R₁₁ to R₂₀ may each independently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a cyano group, a methyl group, anethyl group, an n-propyl group, an isopropyl group, an n-butyl group, anisobutyl group, a sec-butyl group, and a tert-butyl group;

a methyl group, an ethyl group, an n-propyl group, an isopropyl group,an n-butyl group, an isobutyl group, a sec-butyl group, and a tert-butylgroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I and a cyano group; and

a phenyl group, a naphthyl group, and a pyridinyl group, but embodimentsof the present disclosure are not limited thereto.

At least one substituent of the substituted C₃-C₁₀ cycloalkylene group,the substituted C₁-C₁₀ heterocycloalkylene group, the substituted C₃-C₁₀cycloalkenylene group, the substituted C₁-C₁₀ heterocycloalkenylenegroup, the substituted C₆-C₆₀ arylene group, the substituted C₁-C₆₀heteroarylene group, the substituted divalent non-aromatic condensedpolycyclic group, the substituted divalent non-aromatic condensedheteropolycyclic group, the substituted C₁-C₆₀ alkyl group, thesubstituted C₂-C₆₀ alkenyl group, the substituted C₂-C₆₀ alkynyl group,the substituted C₁-C₆₀ alkoxy group, the substituted C₃-C₁₀ cycloalkylgroup, the substituted C₁-C₁₀ heterocycloalkyl group, the substitutedC₃-C₁₀ cycloalkenyl group, the substituted C₁-C₁₀ heterocycloalkenylgroup, the substituted C₆-C₆₀ aryl group, the substituted C₆-C₆₀ aryloxygroup, the substituted C₆-C₆₀ arylthio group, the substituted C₁-C₆₀heteroaryl group, the substituted monovalent non-aromatic condensedpolycyclic group, and the substituted monovalent non-aromatic condensedheteropolycyclic group may be selected from:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group (wherein a carbazolylgroup in the monovalent non-aromatic condensed heteropolycyclic group isexcluded), —Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁),—S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂); and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may each independentlybe selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group,a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkylgroup, a C₁-C₀₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, aC₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ arylgroup substituted with a C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl groupsubstituted with a C₆-C₆₀ aryl group, a terphenyl group, a C₁-C₆₀heteroaryl group, a C₁-C₆₀ heteroaryl group substituted with a C₁-C₆₀alkyl group, a C₁-C₆₀ heteroaryl group substituted with a C₆-C₆₀ arylgroup, a monovalent non-aromatic condensed polycyclic group, and amonovalent non-aromatic condensed heteropolycyclic group.

In one embodiment, the second compound may be represented by Formula 2Aor 2B:

In Formulae 2A and 2B,

M₁₁, A₁₃, A₁₄, Y₁₁ to Y₁₄, T₁₁ to T₁₄, L₁₁ to L₁₆, b11 to b16, R₁₁ toR₁₄, and a11 to a14 may respectively be defined the same as thosedescribed above in connection with Formula 2,

Y₂₁ to Y₂₄ may each independently be N or C,

Y₃₁ to Y₃₄ may each independently be N or C, and

Y₄₁ to Y₄₅ may each independently be N or C.

In one embodiment, the second compound represented by Formula 2 may beat least one compound selected from Compounds BD1 to BD25:

Ph in Compounds BD1 to BD25 indicates a phenyl group.

The second compound represented by Formula 2 has a structure in whichA₁₁ and A₁₄ in Formula 2 are linked to (e.g., linked by) a moietyrepresented by *-(L₁₄)_(b14)-(L₁₆)_(b16)-(L₁₅)_(b15)_*′. The moiety hasa macrocyclic structure in which four or more carbon atoms are includedin the main chain, or two or more carbon atoms and hetero atoms areincluded therein, thereby increasing the structural rigidity of thesecond compound. Although not intended to be limited by any particulartheory, it is believed that interaction between metal atoms is inhibitedor reduced due to the above-described structural characteristics whenthe second compound is included in the organic layer of the organiclight-emitting device, thereby improving the stability and color purityof the organic light-emitting device.

Therefore, the organic light-emitting device including the secondcompound represented by Formula 2 may have a low driving voltage, highcurrent density, and high efficiency.

In addition, the second compound may emit blue light. For example, theorganometallic compound may emit blue light (bottom-emission CIE_(x,y)color coordinates 0.14, 0.06 to 0.08) having a maximum emissionwavelength of about 440 nm to about 495 nm, for example, a maximumemission wavelength of about 450 nm to about 471 nm, but embodiments ofthe present disclosure are not limited thereto. Therefore, theorganometallic compound represented by Formula 1 may be usefully (e.g.,suitably) utilized for manufacture an organic light-emitting device thatemits deep blue light.

In one embodiment, the first compound and the second compound may eachbe included in the emission layer.

In one or more embodiments, the emission layer may include a host and adopant, the host may include the first compound, and the dopant mayinclude the second compound.

In one or more embodiments, the host may include (e.g., further include)a phosphine oxide-containing compound, and the phosphineoxide-containing compound may be different from the first compound.

In one or more embodiments, the first compound and the second compoundmay be included in the emission layer, and an amount of the firstcompound may be larger than an amount of the second compound.

In one embodiment, the first electrode may be an anode, the secondelectrode may be a cathode, the organic layer may further include a holetransport region between the first electrode and the emission layer andan electron transport region between the emission layer and the secondelectrode, the hole transport region may include at least one selectedfrom a hole injection layer, a hole transport layer, a buffer layer, anemission auxiliary layer, and an electron blocking layer, and theelectron transport region may include at least one selected from a holeblocking layer, an electron transport layer, and an electron injectionlayer.

In one embodiment, the hole transport region may include at least one ofa hole injection layer and a hole transport layer, and at least one ofthe hole injection layer and the hole transport layer may include ap-dopant, or (the hole transport region) may include a single filmincluding the p-dopant.

In one or more embodiments, the electron transport region may include ahole blocking layer, and the hole blocking layer may include a phosphineoxide-containing compound and/or a silyl-containing compound.

In one embodiment, the phosphine oxide-containing compound included inthe emission layer may be different from the phosphine oxide-containingcompound included in the hole blocking layer.

According to another embodiment, a flat-panel display apparatusincludes: a thin film transistor including a source electrode, a drainelectrode, and an active layer; and the above-described organiclight-emitting device, wherein the first electrode of the organiclight-emitting device is electrically connected to one of the sourceelectrode and the drain electrode of the thin film transistor.

The synthesis methods of the first compound represented by Formula 1 andthe second compound represented by Formula 2 may be recognizable bythose of ordinary skill in the art by referring to Examples providedbelow.

At least one of the first compounds represented by Formula 1 and atleast one of the second compounds represented by Formula 2 may beutilized between a pair of electrodes of the organic light-emittingdevice. For example, each of the first compound and the second compoundmay be included in at least one of the emission layer and the electrontransport region. In addition, the first compound and the secondcompound may be included in one organic layer, or may be included in twodifferent organic layers. For example, both the first compound and thesecond compound may be present in the emission layer; both the firstcompound and the second compound may be present in the electrontransport region; or the first compound may be present in the emissionlayer, and the second compound may be present in the electron transportregion, but embodiments of the present disclosure are not limitedthereto.

Accordingly, there is provided an organic light-emitting deviceincluding: a first electrode; a second electrode facing the firstelectrode; and an organic layer between the first electrode and thesecond electrode, the organic layer including an emission layer, a firstcompound represented by Formula 1, and a second compound represented byFormula 1.

The expression “an (organic layer) includes a first compound” includes acase in which “an (organic layer) includes a first compound representedby Formula 1” and a case in which “an (organic layer) includes two ormore different first compounds, each represented by Formula 1.”

For example, the organic layer may include, as the first compound, onlyCompound BH1. In this regard, Compound BH1 may exist only in theemission layer of the organic light-emitting device. In one or moreembodiments, the organic layer may include, as the heterocycliccompound, Compound BH1 and Compound BH2. In this regard, Compound BH1and Compound BH2 may exist in the same (i.e., an identical) layer (forexample, Compound BH1 and Compound BH2 may both exist in an emissionlayer), or different layers (for example, Compound BH1 may exist in anemission layer and Compound BH2 may exist in an electron transportlayer).

The expression “an (organic layer) includes a second compound” includesa case in which “an (organic layer) includes a second compoundrepresented by Formula 2” and a case in which “an (organic layer)includes two or more different second compounds, each represented byFormula 2.”

For example, the organic layer may include, as the second compound, onlyCompound BD1. In this regard, Compound BD1 may exist only in theemission layer of the organic light-emitting device. In one or moreembodiments, the organic layer may include, as the heterocycliccompound, Compound BD1 and Compound BD2. In this regard, Compound BD1and Compound BD2 may exist in the same (i.e., an identical) layer (forexample, Compound BD1 and Compound BD2 may both exist in an emissionlayer), or different layers (for example, Compound BD1 may exist in anemission layer and Compound BD2 may exist in an electron transportlayer).

The term “organic layer” used herein refers to a single layer and/or aplurality of layers disposed between the first electrode and the secondelectrode of the organic light-emitting device. A material included inthe “organic layer” is not limited to an organic material.

DESCRIPTION OF THE DRAWING

The drawing is a schematic view of an organic light-emitting device 10according to an embodiment. The organic light-emitting device 10includes a first electrode 110, an organic layer 150, and a secondelectrode 190.

Hereinafter, the structure of the organic light-emitting device 10according to an embodiment and a method of manufacturing the organiclight-emitting device 10 will be described in connection with thedrawing.

In the drawing, a substrate may be additionally disposed under the firstelectrode 110 or above the second electrode 190. The substrate may be aglass substrate or a plastic substrate, each having excellent mechanicalstrength, thermal stability, transparency, surface smoothness, ease ofhandling, and water resistance.

First Electrode 110

The first electrode 110 may be formed by depositing or sputtering amaterial for forming the first electrode 110 on the substrate. When thefirst electrode 110 is an anode, the material for the first electrodemay be selected from materials with a high work function to facilitatehole injection.

The first electrode 110 may be a reflective electrode, asemi-transmissive electrode, or a transmissive electrode. When the firstelectrode 110 is a transmissive electrode, a material for forming thefirst electrode may be selected from indium tin oxide (ITO), indium zincoxide (IZO), tin oxide (SnO₂), zinc oxide (ZnO), and any combinationsthereof, but embodiments of the present disclosure are not limitedthereto. In one or more embodiments, when the first electrode 110 is asemi-transmissive electrode or a reflectable electrode, a material forforming the first electrode may be selected from magnesium (Mg), silver(Ag), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca),magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), and any combinationsthereof, but embodiments of the present disclosure are not limitedthereto.

The first electrode 110 may have a single-layered structure, or amulti-layered structure including two or more layers. For example, thefirst electrode 110 may have a three-layered structure of ITO/Ag/ITO,but the structure of the first electrode 110 is not limited thereto.

The organic layer 150 is disposed on the first electrode 110. Theorganic layer 150 may include an emission layer.

Organic Layer 150

The organic layer may 150 may include the first compound represented byFormula 1 and the second compound represented by Formula 2.

The organic layer 150 may further include a hole transport regionbetween the first electrode 110 and the emission layer, and an electrontransport region between the emission layer and the second electrode190.

Hole Transport Region in Organic Layer 150

The hole transport region may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The hole transport region may include at least one layer selected from ahole injection layer, a hole transport layer, an emission auxiliarylayer, and an electron blocking layer.

For example, the hole transport region may have a single-layeredstructure including a single layer including a plurality of differentmaterials, or a multi-layered structure having a hole injectionlayer/hole transport layer structure, a hole injection layer/holetransport layer/emission auxiliary layer structure, a hole injectionlayer/emission auxiliary layer structure, a hole transportlayer/emission auxiliary layer structure, or a hole injection layer/holetransport layer/electron blocking layer structure, wherein for eachstructure, constituting layers are sequentially stacked from the firstelectrode 110 in this stated order, but the structure of the holetransport region is not limited thereto.

The hole transport region may include at least one selected fromm-MTDATA, TDATA, 2-TNATA, NPB (NPD), β-NPB, TPD, spiro-TPD, spiro-NPB,methylated-NPB, TAPC, HMTPD, 4,4′,4″-tris(N-carbazolyl)triphenylamine(TCTA), polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA),poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate) (PEDOT/PSS),polyaniline/camphor sulfonic acid (PANI/CSA),polyaniline/poly(4-styrenesulfonate) (PANI/PSS), a compound representedby Formula 201, and a compound represented by Formula 202:

In Formulae 201 and 202,

L₂₀₁ to L₂₀₄ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

L₂₀₅ may be selected from *—O—*′, *—S—*′, *—N(Q₂₀₁)-*′, a substituted orunsubstituted C₁-C₂₀ alkylene group, a substituted or unsubstitutedC₂-C₂₀ alkenylene group, a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xa1 to xa4 may each independently be an integer from 0 to 3,

xa5 may be an integer from 1 to 10, and

R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independently be selected from asubstituted or unsubstituted C₃-C₁₀ cycloalkyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkyl group, a substituted orunsubstituted C₃-C₁₀ cycloalkenyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀aryl group, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group.

For example, in Formula 202, R₂₀₁ and R₂₀₂ may optionally be linked viaa single bond, a dimethyl-methylene group, or a diphenyl-methylenegroup, and R₂₀₃ and R₂₀₄ may optionally be linked via a single bond, adimethyl-methylene group, or a diphenyl-methylene group.

In one embodiment, in Formulae 201 and 202, L₂₀₁ to L₂₀₅ may eachindependently be selected from:

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, athiophenylene group, a furanylene group, a carbazolylene group, anindolylene group, an isoindolylene group, a benzofuranylene group, abenzothiophenylene group, a dibenzofuranylene group, adibenzothiophenylene group, a benzocarbazolylene group, adibenzocarbazolylene group, a dibenzosilolylene group, and apyridinylene group; and

a phenylene group, a pentalenylene group, an indenylene group, anaphthylene group, an azulenylene group, a heptalenylene group, anindacenylene group, an acenaphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenalenylene group, a phenanthrenylenegroup, an anthracenylene group, a fluoranthenylene group, atriphenylenylene group, a pyrenylene group, a chrysenylene group, anaphthacenylene group, a picenylene group, a perylenylene group, apentaphenylene group, a hexacenylene group, a pentacenylene group, arubicenylene group, a coronenylene group, an ovalenylene group, athiophenylene group, a furanylene group, a carbazolylene group, anindolylene group, an isoindolylene group, a benzofuranylene group, abenzothiophenylene group, a dibenzofuranylene group, adibenzothiophenylene group, a benzocarbazolylene group, adibenzocarbazolylene group, a dibenzosilolylene group, and apyridinylene group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In one or more embodiments, xa1 to xa4 may each independently be 0, 1,or 2.

In one or more embodiments, xa5 may be 1, 2, 3, or 4.

In one or more embodiments, R₂₀₁ to R₂₀₄ and Q₂₀₁ may each independentlybe selected from:

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a naphthacenyl group, a picenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, arubicenyl group, a coronenyl group, an ovalenyl group, a thiophenylgroup, a furanyl group, a carbazolyl group, an indolyl group, anisoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a pentalenyl group,an indenyl group, a naphthyl group, an azulenyl group, a heptalenylgroup, an indacenyl group, an acenaphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, achrysenyl group, a naphthacenyl group, a picenyl group, a perylenylgroup, a pentaphenyl group, a hexacenyl group, a pentacenyl group, arubicenyl group, a coronenyl group, an ovalenyl group, a thiophenylgroup, a furanyl group, a carbazolyl group, an indolyl group, anisoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, a pyridinylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), and —N(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may respectively be defined the same as described above inconnection with L₂₀₁ to L₂₀₅.

In one or more embodiments, in Formula 201, at least one selected fromR₂₀₁ to R₂₀₃ may each independently be selected from:

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group; and

a fluorenyl group, a spiro-bifluorenyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, a cycloheptyl group, acyclopentenyl group, a cyclohexenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a phenyl group substituted with a C₁-C₁₀ alkylgroup, a phenyl group substituted with —F, a naphthyl group, a fluorenylgroup, a spiro-bifluorenyl group, a carbazolyl group, a dibenzofuranylgroup, and a dibenzothiophenyl group;

but embodiments of the present disclosure are not limited thereto.

In one or more embodiments, in Formula 202, i) R₂₀₁ and R₂₀₂ may belinked via a single bond and/or ii) R₂₀₃ and R₂₀₄ may be linked via asingle bond.

In one or more embodiments, in Formula 202, at least one selected fromR₂₀₁ to R₂₀₄ may be selected from:

a carbazolyl group; and

a carbazolyl group substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, acarbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group;

but embodiments of the present disclosure are not limited thereto.

The compound represented by Formula 201 may be represented by Formula201A:

For example, the compound represented by Formula 201 may be representedby Formula 201A(1), but embodiments of the present disclosure are notlimited thereto:

In one embodiment, the compound represented by Formula 201 may berepresented by Formula 201A-1, but embodiments of the present disclosureare not limited thereto:

In one embodiment, the compound represented 202 by may be represented byFormula 202A:

In one or more embodiments, the compound represented 202 by may berepresented by Formula 202A-1:

In Formulae 201A, 201A(1), 201A-1, 202A, and 202A-1,

L₂₀₁ to L₂₀₃, xa1 to xa3, xa5, and R₂₀₂ to R₂₀₄ may respectively bedefined the same as described above in connection with Formulae 201 and202,

R₂₁₁ and R₂₁₂ may respectively be defined the same as described inconnection with R₂₀₃.

R₂₁₃ to R₂₁₇ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a cyclopentyl group, a cyclohexylgroup, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group,a phenyl group, a biphenyl group, a terphenyl group, a phenyl groupsubstituted with a C₁-C₁₀ alkyl group, a phenyl group substituted with—F, a pentalenyl group, an indenyl group, a naphthyl group, an azulenylgroup, a heptalenyl group, an indacenyl group, an acenaphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a naphthacenyl group, a picenyl group,a perylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a rubicenyl group, a coronenyl group, an ovalenyl group, athiophenyl group, a furanyl group, a carbazolyl group, an indolyl group,an isoindolyl group, a benzofuranyl group, a benzothiophenyl group, adibenzofuranyl group, a dibenzothiophenyl group, a benzocarbazolylgroup, a dibenzocarbazolyl group, a dibenzosilolyl group, and apyridinyl group.

The hole transport region may include at least one compound selectedfrom Compounds HT1 to HT39, but embodiments of the present disclosureare not limited thereto:

A thickness of the hole transport region may be in a range of about 100Å to about 10,000 Å, for example, about 100 Å to about 1,000 Å. When thehole transport region includes at least one of a hole injection layerand a hole transport layer, a thickness of the hole injection layer maybe in a range of about 100 Å to about 9,000 Å, for example, about 100 Åto about 1,000 Å, and a thickness of the hole transport layer may be ina range of about 50 Å to about 2,000 Å, for example about 100 Å to about1,500 Å. When the thicknesses of the hole transport region, the holeinjection layer, and the hole transport layer are within these ranges,satisfactory hole transporting characteristics may be obtained without asubstantial increase in driving voltage.

The emission auxiliary layer may increase light-emission efficiency bycompensating for an optical resonance distance according to thewavelength of light emitted by an emission layer, and the electronblocking layer may block the flow of electrons from an electrontransport region. The emission auxiliary layer and the electron blockinglayer may include the materials as described above.

p-Dopant

The hole transport region may further include, in addition to thesematerials, a charge-generation material for the improvement ofconductive properties. The charge-generation material may behomogeneously or non-homogeneously dispersed in the hole transportregion.

The charge-generation material may be, for example, a p-dopant.

In one embodiment, the p-dopant may have a lowest unoccupied molecularorbital (LUMO) level of −3.5 eV or less.

The p-dopant may include at least one selected from a quinonederivative, a metal oxide, and a cyano group-containing compound, butembodiments of the present disclosure are not limited thereto.

For example, the p-dopant may include at least one selected from:

a quinone derivative, such as tetracyanoquinodimethane (TCNQ) and2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ);

a metal oxide, such as tungsten oxide and molybdenum oxide;

1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile (HAT-CN); and

a compound represented by Formula 221,

but embodiments of the present disclosure are not limited thereto:

In Formula 221,

R₂₂₁ to R₂₂₃ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₁-C₆₀ heteroaryl group, asubstituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, wherein at least oneselected from R₂₂₁ to R₂₂₃ may have at least one substituent selectedfrom a cyano group, —F, —Cl, —Br, —I, a C₁-C₂₀ alkyl group substitutedwith —F, a C₁-C₂₀ alkyl group substituted with —Cl, a C₁-C₂₀ alkyl groupsubstituted with —Br, and a C₁-C₂₀ alkyl group substituted with —I.

Emission Layer in Organic Layer 150

When the organic light-emitting device 10 is a full-color organiclight-emitting device, the emission layer may be patterned into a redemission layer, a green emission layer, or a blue emission layer,according to a sub-pixel. In one or more embodiments, the emission layermay have a stacked structure of two or more layers selected from a redemission layer, a green emission layer, and a blue emission layer, inwhich the two or more layers contact each other or are separated fromeach other. In one or more embodiments, the emission layer may includetwo or more materials selected from a red light-emitting material, agreen light-emitting material, and a blue light-emitting material, inwhich the two or more materials are mixed with each other in a singlelayer to emit white light.

The emission layer may include the first compound represented by Formula1 and the second compound represented by Formula 2.

The emission layer may include a host and a dopant. The dopant mayinclude at least one selected from a phosphorescent dopant and afluorescent dopant.

The host may include the first compound, and the dopant may include thesecond compound. For example, the dopant may include a phosphorescentdopant, and the phosphorescent dopant may include the second compound.

An amount of the dopant in the emission layer may be in a range of about0.01 parts by weight to about 15 parts by weight based on 100 parts byweight of the host, but embodiments of the present disclosure are notlimited thereto.

A thickness of the emission layer may be in a range of about 100 Å toabout 1,000 Å, for example, about 200 Å to about 600 Å. When thethickness of the emission layer is within this range, excellentlight-emission characteristics may be obtained without a substantialincrease in driving voltage.

Host in Emission Layer

In one or more embodiments, the host may further include, in addition tothe first compound, a compound represented by Formula 301:

[Ar₃₀₁]_(xb11)-[(L₃₀₁)_(xb1)-R₃₀₁]_(xb21),  Formula 301

In Formula 301,

Ar₃₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

xb11 may be 1, 2, or 3,

L₃₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xb1 may be an integer from 0 to 5,

R₃₀₁ may be selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group,a cyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a substituted or unsubstituted C₁-C₆₀ alkyl group, asubstituted or unsubstituted C₂-C₆₀ alkenyl group, a substituted orunsubstituted C₂-C₆₀ alkynyl group, a substituted or unsubstitutedC₁-C₆₀ alkoxy group, a substituted or unsubstituted C₃-C₁₀ cycloalkylgroup, a substituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —Si(Q₃₀₁)(Q₃₀₂)(Q₃₀₃), —N(Q₃₀₁)(Q₃₀₂),—B(Q₃₀₁)(Q₃₀₂), —C(═O)(Q₃₀₁), —S(═O)₂(Q₃₀₁), and —P(═O)(Q₃₀₁)(Q₃₀₂),

xb21 may be an integer from 1 to 5, and

Q₃₀₁ to Q₃₀₃ may each independently be selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group, but embodiments of the presentdisclosure are not limited thereto.

In one embodiment, Ar₃₀₁ in Formula 301 may be selected from:

a naphthalene group, a fluorene group, a spiro-bifluorene group, abenzofluorene group, a dibenzofluorene group, a phenalene group, aphenanthrene group, an anthracene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a naphthacenegroup, a picene group, a perylene group, a pentaphene group, anindenoanthracene group, a dibenzofuran group, and a dibenzothiophenegroup; and

a naphthalene group, a fluorene group, a spiro-bifluorene group, abenzofluorene group, a dibenzofluorene group, a phenalene group, aphenanthrene group, an anthracene group, a fluoranthene group, atriphenylene group, a pyrene group, a chrysene group, a naphthacenegroup, a picene group, a perylene group, a pentaphene group, anindenoanthracene group, a dibenzofuran group, and a dibenzothiophenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, a naphthyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂),—C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group, but embodiments of the present disclosureare not limited thereto.

When xb11 in Formula 301 is two or more, two or more Ar₃₀₁(s) may belinked via a single bond.

In one or more embodiments, the compound represented by Formula 301 maybe represented by Formula 301-1 or 301-2:

wherein in Formulae 301-1 and 301-2,

A₃₀₁ to A₃₀₄ may each independently be selected from benzene, anaphthalene, a phenanthrene, a fluoranthene, a triphenylene, a pyrene, achrysene, a pyridine, a pyrimidine, an indene, a fluorene, aspiro-bifluorene, a benzofluorene, a dibenzofluorene, an indole, acarbazole, benzocarbazole, dibenzocarbazole, a furan, a benzofuran, adibenzofuran, a naphthofuran, a benzonaphthofuran, dinaphthofuran, athiophene, a benzothiophene, a dibenzothiophene, a naphthothiophene, abenzonaphthothiophene group, and a dinaphthothiophene group,

X₃₀₁ may be O, S, or N-[(L₃₀₄)_(xb4)-R₃₀₄],

R₃₁₁ to R₃₁₄ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂),

xb22 and xb23 may each independently be 0, 1, or 2,

L₃₀₁, xb1, R₃₀₁, and Q₃₁ to Q₃₃ may respectively be defined the same asdescribed above in connection with Formula 301,

L₃₀₂ to L₃₀₄ may each independently be defined the same as described inconnection with L₃₀₁,

xb2 to xb4 may each independently be defined the same as described inconnection with xb1,

R₃₀₂ to R₃₀₄ may each independently be defined the same as described inconnection with R₃₀₁.

For example, in Formulae 301, 301-1, and 301-2, L₃₀₁ to L₃₀₄ may eachindependently be selected form:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, anoxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, an azacarbazolyl group, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂),—B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may respectively be defined the same as described above inconnection with Formula 301.

In one embodiment, in Formulae 301, 301-1, and 301-2, R₃₀₁ to R₃₀₄ mayeach independently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group, a furanyl group, a carbazolyl group, anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, an azacarbazolylgroup, —Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may respectively be defined the same as described above inconnection with Formula 301.

In one or more embodiments, the host may include an alkaline earth metalcomplex. For example, the host may be selected from a Be complex (forexample, Compound H55), a Mg complex, and a Zn complex.

The host may include at least one selected from9,10-di(2-naphthyl)anthracene (ADN),2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN),9,10-di-(2-naphthyl)-2-t-butyl-anthracene (TBADN),4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), 1,3-di-9-carbazolylbenzene(mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), and Compounds H1 to H55,but embodiments of the present disclosure are not limited thereto:

Phosphorescent Dopant Included in Emission Layer in Organic Layer 150

The phosphorescent dopant may include the second compound.

The phosphorescent dopant may include an organometallic complexrepresented by Formula 401 below:

In Formulae 401 and 402,

M may be selected from iridium (Ir), platinum (Pt), palladium (Pd),osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu),terbium (Tb), rhodium (Rh), and thulium (Tm),

L₄₀₁ may be selected from ligands represented by Formula 402, and xc1may be 1, 2, or 3, wherein, when xc1 is two or more, two or more L₄₀₁(s)may be identical to or different from each other,

L₄₀₂ may be an organic ligand, and xc2 may be an integer from 0 to 4,wherein, when xc2 is two or more, two or more L₄₀₂(s) may be identicalto or different from each other,

X₄₀₁ to X₄₀₄ may each independently be nitrogen or carbon;

X₄₀₁ and X₄₀₃ may be linked via a single bond or a double bond, and X₄₀₂and X₄₀₄ may be linked via a single bond or a double bond,

A₄₀₁ and A₄₀₂ may each independently be a C₅-C₆₀ carbocyclic group or aC₁-C₆₀ heterocyclic group,

X₄₀₅ may be a single bond, *—O—*′, *—S—*′, *—C(═O)—*′, *—N(Q₄₁₁)-*′,*—C(Q₄₁₁)(Q₄₁₂)-*′, *—C(Q₄₁₁)═C(Q₄₁₂)*′, *—O(Q₄₁₁)═*′, or *═O(Q₄₁₁)=*′,wherein Q₄₁₁ and Q₄₁₂ may be hydrogen, deuterium, a C₁-C₂₀ alkyl group,a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, or a naphthyl group,

X₄₀₆ may be a single bond, O, or S,

R₄₀₁ and R₄₀₂ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₂₀ alkyl group, a substituted orunsubstituted C₁-C₂₀ alkoxy group, a substituted or unsubstituted C₃-C₀₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃),—N(Q₄₀₁)(Q₄₀₂), —B(Q₄₀₁)(Q₄₀₂), —C(═O)(Q₄₀₁), —S(═O)₂(Q₄₀₁), and—P(═O)(Q₄₀₁)(Q₄₀₂), wherein Q₄₀₁ to Q₄₀₃ may each independently beselected from a C₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, a C₆-C₂₀ arylgroup, and a C₁-C₂₀ heteroaryl group,

xc11 and xc12 may each independently be an integer from 0 to 10, and

* and *′ in Formula 402 each indicate a binding site to M of Formula401.

In one embodiment, in Formula 402, A₄₀₁ and A₄₀₂ may each independentlybe selected from a benzene group, a naphthalene group, a fluorene group,a spiro-bifluorene group, an indene group, a pyrrole group, a thiophenegroup, a furan group, an imidazole group, a pyrazole group, a thiazolegroup, an isothiazole group, an oxazole group, an isoxazole group, apyridine group, a pyrazine group, a pyrimidine group, a pyridazinegroup, a quinoline group, an isoquinoline group, a benzoquinoline group,a quinoxaline group, a quinazoline group, a carbazole group, abenzimidazole group, a benzofuran group, a benzothiophene group, anisobenzothiophene group, a benzoxazole group, an isobenzoxazole group, atriazole group, a tetrazole group, an oxadiazole group, a triazinegroup, a dibenzofuran group, and a dibenzothiophene group.

In one or more embodiments, in Formula 402, i) X₄₀₁ may be nitrogen, andX₄₀₂ may be carbon, or ii) X₄₀₁ and X₄₀₂ may each be nitrogen at thesame time.

In one or more embodiments, in Formula 402, R₄₀₁ and R₄₀₂ may eachindependently be selected from:

hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₂₀ alkyl group, and a C₁-C₂₀ alkoxy group;

a C₁-C₂₀ alkyl group and a C₁-C₂₀ alkoxy group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a phenyl group, a naphthyl group, a cyclopentyl group,a cyclohexyl group, an adamantanyl group, a norbornanyl group, and anorbornenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a fluorenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group;

a cyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group a phenyl group, a biphenyl group,a terphenyl group, a naphthyl group, a fluorenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, atriazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, acyclopentyl group, a cyclohexyl group, an adamantanyl group, anorbornanyl group, a norbornenyl group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a fluorenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, aquinoxalinyl group, a quinazolinyl group, a carbazolyl group, adibenzofuranyl group, and a dibenzothiophenyl group; and

—Si(Q₄₀₁)(Q₄₀₂)(Q₄₀₃), —N(Q₄₀₁)(Q₄₀₂), —B(Q₄₀₁)(Q₄₀₂), —C(═O)(Q₄₀₁),—S(═O)₂(Q₄₀₁), and —P(═O)(Q₄₀₁)(Q₄₀₂), and

Q₄₀₁ to Q₄₀₃ may each independently be selected from a C₁-C₁₀ alkylgroup, a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, and anaphthyl group, but embodiments of the present disclosure are notlimited thereto.

In one or more embodiments, in Formula 401, when xc1 is two or more, twoA₄₀₁(s) among a plurality of L₄₀₁(S) may optionally be linked via alinking group, X₄₀₇, or two A₄₀₂(s) may optionally be linked via alinking group, X₄₀₈ (see Compounds PD1 to PD4 and PD7). X₄₀₇ and X₄₀₈may each independently be a single bond, *—O—*′, *—S—*′, *—C(═O)—*′,*—N(Q₄₁₃)-*′, *—C(Q₄₁₃)(Q₄₁₄)-*′, or *—C(Q₄₁₃)=C(Q₄₁₄)-*′ (wherein Q₄₁₃and Q₄₁₄ may each independently be hydrogen, deuterium, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group or a naphthyl group), but embodiments of the presentdisclosure are not limited thereto.

L₄₀₂ in Formula 401 may be a monovalent, divalent, or trivalent organicligand. For example, L₄₀₂ may be selected from halogen, diketone (forexample, acetylacetonate), carboxylic acid (for example, picolinate),—C(═O), isonitrile, —CN, and phosphorus (for example, phosphine, orphosphite), but embodiments of the present disclosure are not limitedthereto.

In one or more embodiments, the phosphorescent dopant may be selectedfrom, for example, Compounds PD1 to PD25, but embodiments of the presentdisclosure are not limited thereto:

Fluorescent Dopant in Emission Layer

The fluorescent dopant may include an arylamine compound and/or astyrylamine compound.

The fluorescent dopant may include a compound represented by Formula501:

In Formula 501,

Ar₅₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

L₅₀₁ to L₅₀₃ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xd1 to xd3 may each independently be an integer from 0 to 3;

R₅₀₁ and R₅₀₂ may each independently be selected from a substituted orunsubstituted C₃-C₁₀ cycloalkyl group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkyl group, a substituted or unsubstituted C₃-C₁₀cycloalkenyl group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenyl group, a substituted or unsubstituted C₆-C₆₀ arylgroup, a substituted or unsubstituted C₆-C₆₀ aryloxy group, asubstituted or unsubstituted C₆-C₆₀ arylthio group, a substituted orunsubstituted C₁-C₆₀ heteroaryl group, a substituted or unsubstitutedmonovalent non-aromatic condensed polycyclic group, and a substituted orunsubstituted monovalent non-aromatic condensed heteropolycyclic group,and

xd4 may be an integer from 1 to 6.

In one embodiment, Ar₅₀₁ in Formula 501 may be selected from:

a naphthalene group, a heptalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, and an indenophenanthrenegroup; and

a naphthalene group, a heptalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, and an indenophenanthrenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, aC₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In one or more embodiments, L₅₀₁ to L₅₀₃ in Formula 501 may eachindependently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, and a pyridinylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, and a pyridinylene group, each substituted withat least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group.

In one or more embodiments, in Formula 501, R₅₀₁ and R₅₀₂ may eachindependently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group; and

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, and a pyridinyl group, each substituted with atleast one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenylgroup, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, and —Si(Q₃₁)(Q₃₂)(Q₃₃), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

In one or more embodiments, xd4 in Formula 501 may be 2, but embodimentsof the present disclosure are not limited thereto.

For example, the fluorescent dopant may be selected from Compounds FD1to FD22:

In one or more embodiments, the fluorescent dopant may be selected fromthe following compounds, but embodiments of the present disclosure arenot limited thereto.

Electron Transport Region in Organic Layer 150

The electron transport region may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The electron transport region may include at least one selected from abuffer layer, a hole blocking layer, an electron control layer, anelectron transport layer, and an electron injection layer, butembodiments of the present disclosure are not limited thereto.

For example, the electron transport region may have an electrontransport layer/electron injection layer structure, a hole blockinglayer/electron transport layer/electron injection layer structure, anelectron control layer/electron transport layer/electron injection layerstructure, or a buffer layer/electron transport layer/electron injectionlayer structure, wherein for each structure, constituting layers aresequentially stacked from an emission layer. However, embodiments of thestructure of the electron transport region are not limited thereto.

The electron transport region (for example, a buffer layer, a holeblocking layer, an electron control layer, or an electron transportlayer in the electron transport region) may include a metal-freecompound containing at least one π electron-depleted nitrogen-containingring.

The term “π electron-depleted nitrogen-containing ring” refers to aC₁-C₆₀ heterocyclic group having at least one *—N═*′ moiety as aring-forming moiety.

For example, the “π electron-depleted nitrogen-containing ring” may bei) a 60-membered to 7-membered heteromonocyclic group having at leastone *—N═*′ moiety, ii) a heteropolycyclic group in which two or more5-membered to 7-membered heteromonocyclic groups each having at leastone *—N═*′ moiety are condensed with each other, or iii) aheteropolycyclic group in which at least one of 5-membered to 7-memberedheteromonocyclic groups, each having at least one *—N═*′ moiety, iscondensed with at least one C₅-C₆₀ carbocyclic group.

Examples of the π electron-depleted nitrogen-containing ring include animidazole, a pyrazole, a thiazole, an isothiazole, an oxazole, anisoxazole, a pyridine, a pyrazine, a pyrimidine, a pyridazine, anindazole, a purine, a quinoline, an isoquinoline, a benzoquinoline, aphthalazine, a naphthyridine, a quinoxaline, a quinazoline, a cinnoline,a phenanthridine, an acridine, a phenanthroline, a phenazine, abenzimidazole, an isobenzothiazole, a benzoxazole, an isobenzoxazole, atriazole, a tetrazole, an oxadiazole, a triazine, thiadiazol, animidazopyridine, an imidazopyrimidine, and an azacarbazole, butembodiments of the present disclosure are not limited thereto.

For example, the electron transport region may include a compoundrepresented by Formula 601:

[Ar₆₀₁]_(xe11)-[(L₆₀₁)_(xe1)-R₆₀₁]_(xe21)  Formula 601

In Formula 601,

Ar₆₀₁ may be a substituted or unsubstituted C₅-C₆₀ carbocyclic group ora substituted or unsubstituted C₁-C₆₀ heterocyclic group,

xe11 may be 1, 2, or 3,

L₆₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, and a substituted or unsubstituted divalentnon-aromatic condensed heteropolycyclic group,

xe1 may be an integer from 0 to 5,

R₆₀₁ may be selected from a substituted or unsubstituted C₃-C₁₀cycloalkyl group, a substituted or unsubstituted C₁-C₁₀ heterocycloalkylgroup, a substituted or unsubstituted C₃-C₁₀ cycloalkenyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkenyl group, asubstituted or unsubstituted C₆-C₆₀ aryl group, a substituted orunsubstituted C₆-C₆₀ aryloxy group, a substituted or unsubstitutedC₆-C₆₀ arylthio group, a substituted or unsubstituted C₁-C₆₀ heteroarylgroup, a substituted or unsubstituted monovalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₆₀₁)(Q₆₀₂)(Q₆₀₃), —C(═O)(Q₆₀₁),—S(═O)₂(Q₆₀₁), and —P(═O)(Q₆₀₁)(Q₆₀₂), and

Q₆₀₁ to Q₆₀₃ may each independently be a C₁-C₁₀ alkyl group, a C₁-C₁₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or anaphthyl group, and

xe21 may be an integer from 1 to 5.

In one embodiment, at least one of Ar₆₀₁(s) in the number of xe11 andR601(s) in the number of xe21 may include the π electron-depletednitrogen-containing ring

In one embodiment, in Formula 601, ring Ar₆₀₁ may be selected from:

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, a dibenzofuran group, adibenzothiophene group, a carbazole group, an imidazole group, apyrazole group, a thiazole group, an isothiazole group, an oxazolegroup, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indazole group, a purine group,a quinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, an isobenzothiazole group, a benzoxazole group, anisobenzoxazole group, a triazole group, a tetrazole group, an oxadiazolegroup, a triazine group, a thiadiazole group, an imidazopyridine group,an imidazopyrimidine group, and an azacarbazole group; and

a benzene group, a naphthalene group, a fluorene group, aspiro-bifluorene group, a benzofluorene group, a dibenzofluorene group,a phenalene group, a phenanthrene group, an anthracene group, afluoranthene group, a triphenylene group, a pyrene group, a chrysenegroup, a naphthacene group, a picene group, a perylene group, apentaphene group, an indenoanthracene group, a dibenzofuran group, adibenzothiophene group, a carbazole group, an imidazole group, apyrazole group, a thiazole group, an isothiazole group, an oxazolegroup, an isoxazole group, a pyridine group, a pyrazine group, apyrimidine group, a pyridazine group, an indazole group, a purine group,a quinoline group, an isoquinoline group, a benzoquinoline group, aphthalazine group, a naphthyridine group, a quinoxaline group, aquinazoline group, a cinnoline group, a phenanthridine group, anacridine group, a phenanthroline group, a phenazine group, abenzimidazole group, an isobenzothiazole group, a benzoxazole group, anisobenzoxazole group, a triazole group, a tetrazole group, an oxadiazolegroup, a triazine group, a thiadiazole group, an imidazopyridine group,an imidazopyrimidine group, and an azacarbazole group, each substitutedwith at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, a naphthyl group,—Si(Q₃₁)(Q₃₂)(Q₃₃), —S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₃₁ to Q₃₃ may each independently be selected from a C₁-C₁₀ alkyl group,a C₁-C₁₀ alkoxy group, a phenyl group, a biphenyl group, a terphenylgroup, and a naphthyl group.

When xe1 in Formula 601 is two or more, two or more Ar₆₀₁(s) may belinked via a single bond.

In one or more embodiments, Ar₆₀₁ in Formula 601 may be an anthracenegroup.

In one or more embodiments, the compound represented by 601 may berepresented by Formula 601-1:

In Formula 601-1,

X₆₁₄ may be N or C(R₆₁₄), X₆₁₅ may be N or C(R₆₁₅), and X₆₁₆ may be N orC(R₆₁₆), wherein at least one selected from X₆₁₄ to X₆₁₆ may be N,

L₆₁₁ to L₆₁₃ may each independently be defined the same as described inconnection with L₆₀₁,

xe611 to xe613 may each independently be defined the same as describedin connection with xe1,

R₆₁₁ to R₆₁₃ may each independently be defined the same as described inconnection with R₆₀₁, and

R₆₁₄ to R₆₁₆ may each independently be selected from hydrogen,deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group.

In one embodiment, L₆₀₁ and L₆₁₁ to L₆₁₃ in Formulae 601 and 601-1 mayeach independently be selected from:

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group; and

a phenylene group, a naphthylene group, a fluorenylene group, aspiro-bifluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a fluoranthenylene group, a triphenylenylene group, a pyrenylenegroup, a chrysenylene group, a perylenylene group, a pentaphenylenegroup, a hexacenylene group, a pentacenylene group, a thiophenylenegroup, a furanylene group, a carbazolylene group, an indolylene group,an isoindolylene group, a benzofuranylene group, a benzothiophenylenegroup, a dibenzofuranylene group, a dibenzothiophenylene group, abenzocarbazolylene group, a dibenzocarbazolylene group, adibenzosilolylene group, a pyridinylene group, an imidazolylene group, apyrazolylene group, a thiazolylene group, an isothiazolylene group, anoxazolylene group, an isoxazolylene group, a thiadiazolylene group, anoxadiazolylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a triazinylene group, a quinolinylene group, anisoquinolinylene group, a benzoquinolinylene group, a phthalazinylenegroup, a naphthyridinylene group, a quinoxalinylene group, aquinazolinylene group, a cinnolinylene group, a phenanthridinylenegroup, an acridinylene group, a phenanthrolinylene group, aphenazinylene group, a benzimidazolylene group, an isobenzothiazolylenegroup, a benzoxazolylene group, an isobenzoxazolylene group, atriazolylene group, a tetrazolylene group, an imidazopyridinylene group,an imidazopyrimidinylene group, and an azacarbazolylene group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, a fluorenyl group, a spiro-bifluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenylgroup, a hexacenyl group, a pentacenyl group, a thiophenyl group, afuranyl group, a carbazolyl group, an indolyl group, an isoindolylgroup, a benzofuranyl group, a benzothiophenyl group, a dibenzofuranylgroup, a dibenzothiophenyl group, a benzocarbazolyl group, adibenzocarbazolyl group, a dibenzosilolyl group, a pyridinyl group, animidazolyl group, a pyrazolyl group, a thiazolyl group, an isothiazolylgroup, an oxazolyl group, an isoxazolyl group, a thiadiazolyl group, anoxadiazolyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a triazinyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a phthalazinyl group, a naphthyridinyl group, aquinoxalinyl group, a quinazolinyl group, a cinnolinyl group, aphenanthridinyl group, an acridinyl group, a phenanthrolinyl group, aphenazinyl group, a benzimidazolyl group, an isobenzothiazolyl group, abenzoxazolyl group, an isobenzoxazolyl group, a triazolyl group, atetrazolyl group, an imidazopyridinyl group, an imidazopyrimidinylgroup, and an azacarbazolyl group;

but embodiments of the present disclosure are not limited thereto.

In one or more embodiments, xe1 and xe611 to xe613 in Formulae 601 and601-1 may each independently be 0, 1, or 2.

In one or more embodiments, in Formulae 601 and 601-1, R₆₀₁ and R₆₁₁ toR₆₁₃ may each independently be selected from:

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group;

a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, afluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, adibenzofluorenyl group, a phenanthrenyl group, an anthracenyl group, afluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenylgroup, a perylenyl group, a pentaphenyl group, a hexacenyl group, apentacenyl group, a thiophenyl group, a furanyl group, a carbazolylgroup, an indolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group, each substituted with at least one selected fromdeuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₂₀alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, aspiro-bifluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a fluoranthenylgroup, a triphenylenyl group, a pyrenyl group, a chrysenyl group, aperylenyl group, a pentaphenyl group, a hexacenyl group, a pentacenylgroup, a thiophenyl group, a furanyl group, a carbazolyl group, anindolyl group, an isoindolyl group, a benzofuranyl group, abenzothiophenyl group, a dibenzofuranyl group, a dibenzothiophenylgroup, a benzocarbazolyl group, a dibenzocarbazolyl group, adibenzosilolyl group, a pyridinyl group, an imidazolyl group, apyrazolyl group, a thiazolyl group, an isothiazolyl group, an oxazolylgroup, an isoxazolyl group, a thiadiazolyl group, an oxadiazolyl group,a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, a triazinylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a phthalazinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a cinnolinyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a benzimidazolyl group, an isobenzothiazolyl group, a benzoxazolylgroup, an isobenzoxazolyl group, a triazolyl group, a tetrazolyl group,an imidazopyridinyl group, an imidazopyrimidinyl group, and anazacarbazolyl group; and

—S(═O)₂(Q₆₀₁) and —P(═O)(Q₆₀₁)(Q₆₀₂), and

Q₆₀₁ and Q₆₀₂ may respectively be defined the same as described above.

The electron transport region may include at least one compound selectedfrom Compounds ET1 to ET36, but embodiments of the present disclosureare not limited thereto:

In one or more embodiments, the electron transport region may include atleast one compound selected from2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP),4,7-diphenyl-1,10-phenanthroline (Bphen), Alq₃, BAlq,3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole(TAZ), and NTAZ.

A thickness of the buffer layer, the hole blocking layer, or theelectron control layer may be in a range of about 20 Å to about 1,000 Å,for example, about 30 Å to about 300 Å. When the thicknesses of thebuffer layer, the hole blocking layer, and the electron control layerare within these ranges, the electron blocking layer may have excellentelectron blocking characteristics or electron control characteristicswithout a substantial increase in driving voltage.

A thickness of the electron transport layer may be in a range of about100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. Whenthe thickness of the electron transport layer is within the rangedescribed above, the electron transport layer may have satisfactoryelectron transport characteristics without a substantial increase indriving voltage.

The electron transport region (for example, the electron transport layerin the electron transport region) may further include, in addition tothe materials described above, a metal-containing material.

The metal-containing material may include at least one selected fromalkali metal complex and alkaline earth-metal complex. The alkali metalcomplex may include a metal ion selected from a Li ion, a Na ion, a Kion, a Rb ion, and a Cs ion, and the alkaline earth-metal complex mayinclude a metal ion selected from a Be ion, a Mg ion, a Ca ion, a Srion, and a Ba ion. A ligand coordinated with the metal ion of the alkalimetal complex or the alkaline earth-metal complex may be selected from ahydroxy quinoline, a hydroxy isoquinoline, a hydroxy benzoquinoline, ahydroxy acridine, a hydroxy phenanthridine, a hydroxy phenyloxazole, ahydroxy phenylthiazole, a hydroxy diphenyloxadiazole, a hydroxydiphenylthiadiazol, a hydroxy phenylpyridine, a hydroxyphenylbenzimidazole, a hydroxy phenylbenzothiazole, a bipyridine, aphenanthroline, and a cyclopentadiene, but embodiments of the presentdisclosure are not limited thereto.

For example, the metal-containing material may include a Li complex. TheLi complex may include, for example, Compound ET-D1 (lithium quinolate,LiQ) or ET-D2.

The electron transport region may include an electron injection layerthat facilitates injection of electrons from the second electrode 190.The electron injection layer may directly contact the second electrode190.

The electron injection layer may have i) a single-layered structureincluding a single layer including a single material, ii) asingle-layered structure including a single layer including a pluralityof different materials, or iii) a multi-layered structure having aplurality of layers including a plurality of different materials.

The electron injection layer may include an alkali metal, an alkalineearth metal, a rare earth metal, an alkali metal compound, an alkalineearth-metal compound, a rare earth metal compound, an alkali metalcomplex, an alkaline earth-metal complex, a rare earth metal complex, orany combinations thereof.

The alkali metal may be selected from Li, Na, K, Rb, and Cs. In oneembodiment, the alkali metal may be Li, Na, or Cs. In one or moreembodiments, the alkali metal may be Li or Cs, but embodiments of thepresent disclosure are not limited thereto.

The alkaline earth metal may be selected from Mg, Ca, Sr, and Ba.

The rare earth metal may be selected from Sc, Y, Ce, Tb, Yb, and Gd.

The alkali metal compound, the alkaline earth-metal compound, and therare earth metal compound may be selected from oxides and halides (forexample, fluorides, chlorides, bromides, or iodides) of the alkalimetal, the alkaline earth-metal, and the rare earth metal.

The alkali metal compound may be selected from alkali metal oxides (suchas Li₂O, Cs₂O, or K₂O), and alkali metal halides (such as LiF, NaF, CsF,KF, LiI, NaI, CsI, KI, or RbI). In one embodiment, the alkali metalcompound may be selected from LiF, Li₂O, NaF, LiI, NaI, CsI, and KI, butembodiments of the present disclosure are not limited thereto.

The alkaline earth-metal compound may be selected from alkalineearth-metal compounds, such as BaO, SrO, CaO, Ba_(x)Sr_(1-x)O (0<x<1),or Ba_(x)Ca_(1-x)O (0<x<1). In one embodiment, the alkaline earth-metalcompound may be selected from BaO, SrO, and CaO, but embodiments of thepresent disclosure are not limited thereto.

The rare earth metal compound may be selected from YbF₃, ScF₃, ScO₃,Y₂O₃, Ce₂O₃, GdF₃, and TbF₃. In one embodiment, the rare earth metalcompound may be selected from YbF3, ScF₃, TbF₃, YbI₃, ScI₃, and TbI₃,but embodiments of the present disclosure are not limited thereto.

The alkali metal complex, the alkaline earth-metal complex, and the rareearth metal complex may include an ion of alkali metal, alkalineearth-metal, and rare earth metal as described above, and a ligandcoordinated with a metal ion of the alkali metal complex, the alkalineearth-metal complex, or the rare earth metal complex may be selectedfrom hydroxy quinoline, hydroxy isoquinoline, hydroxy benzoquinoline,hydroxy acridine, hydroxy phenanthridine, hydroxy phenyloxazole, hydroxyphenylthiazole, hydroxy diphenyloxadiazole, hydroxy diphenylthiadiazol,hydroxy phenylpyridine, hydroxy phenylbenzimidazole, hydroxyphenylbenzothiazole, bipyridine, phenanthroline, and cyclopentadiene,but embodiments of the present disclosure are not limited thereto.

The electron injection layer may include (e.g., consist of) an alkalimetal, an alkaline earth metal, a rare earth metal, an alkali metalcompound, an alkaline earth-metal compound, a rare earth metal compound,an alkali metal complex, an alkaline earth-metal complex, a rare earthmetal complex, or any combinations thereof, as described above. In oneor more embodiments, the electron injection layer may further include anorganic material. When the electron injection layer further includes anorganic material, an alkali metal, an alkaline earth metal, a rare earthmetal, an alkali metal compound, an alkaline earth-metal compound, arare earth metal compound, an alkali metal complex, an alkalineearth-metal complex, a rare earth metal complex, or any combinationsthereof may be homogeneously or non-homogeneously dispersed in a matrixincluding the organic material.

A thickness of the electron injection layer may be in a range of about 1Å to about 100 Å, for example, about 3 Å to about 90 Å. When thethickness of the electron injection layer is within the range describedabove, the electron injection layer may have satisfactory electroninjection characteristics without a substantial increase in drivingvoltage.

Second Electrode 190

The second electrode 190 may be disposed on the organic layer 150 havingsuch a structure. The second electrode 190 may be a cathode which is anelectron injection electrode, and in this regard, a material for formingthe second electrode 190 may be selected from metal, an alloy, anelectrically conductive compound, and a combination thereof, which havea relatively low work function.

The second electrode 190 may include at least one selected from lithium(Li), silver (Ag), magnesium (Mg), aluminum (Al), aluminum-lithium(Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver(Mg—Ag), ITO, and IZO, but embodiments of the present disclosure are notlimited thereto. The second electrode 190 may be a transmissiveelectrode, a semi-transmissive electrode, or a reflective electrode.

The second electrode 190 may have a single-layered structure, or amulti-layered structure including two or more layers.

Hereinbefore, the organic light-emitting device has been described withreference to the drawing, but embodiments of the present disclosure arenot limited thereto.

Layers constituting the hole transport region, the emission layer, andlayers constituting the electron transport region may be formed in acertain region utilizing one or more suitable methods selected fromvacuum deposition, spin coating, casting, Langmuir-Blodgett (LB)deposition, ink-jet printing, laser-printing, and laser-induced thermalimaging.

When layers constituting the hole transport region, the emission layer,and layers constituting the electron transport region are formed byvacuum deposition, the deposition may be performed at a depositiontemperature of about 100° C. to about 500° C., a vacuum degree of about10⁻⁸ torr to about 10⁻³ torr, and a deposition speed of about 0.01 Å/secto about 100 Å/sec by taking into account a material to be included in alayer to be formed, and the structure of a layer to be formed.

When layers constituting the hole transport region, the emission layer,and layers constituting the electron transport region are formed by spincoating, the spin coating may be performed at a coating speed of about2,000 rpm to about 5,000 rpm and at a heat treatment temperature ofabout 80° C. to about 200° C. by taking into account a material to beincluded in a layer to be formed, and the structure of a layer to beformed.

A flat display apparatus according to another aspect of the presentdisclosure may include: the organic light-emitting device and atransistor, wherein the transistor includes a source electrode, a drainelectrode, a gate electrode, and an activation layer, and the firstelectrode of the organic light-emitting device is electrically connectedto at least one of the source electrode and the drain electrode of thetransistor.

The activation layer of the transistor may be modified to an amorphoussilicon layer, a crystalline silicon layer, an organic semiconductivelayer, or an oxide semiconductive layer.

Such a flat display may prevent or reduce red and green emission in ablack state, thereby improving brightness-dependent emission efficiency.

General Definition of Substituents

The term “0C₁-C₆₀ alkyl group” as used herein refers to a linear orbranched aliphatic saturated hydrocarbon monovalent group having 1 to 60carbon atoms, and examples thereof include a methyl group, an ethylgroup, a propyl group, an isobutyl group, a sec-butyl group, atert-butyl group, a pentyl group, an isoamyl group, and a hexyl group.The term “C₁-C₆₀ alkylene group” as used herein refers to a divalentgroup having the same structure as the C₁-C₆₀ alkyl group.

The term “C₂-C₆₀ alkenyl group” as used herein refers to a hydrocarbongroup having at least one carbon-carbon double bond in the middle or atthe terminus of the C₂-C₆₀ alkyl group, and examples thereof include anethenyl group, a propenyl group, and a butenyl group. The term “C₂-C₆₀alkenylene group” as used herein refers to a divalent group having thesame structure as the C₂-C₆₀ alkenyl group.

The term “C₂-C₆₀ alkynyl group” as used herein refers to a hydrocarbongroup having at least one carbon-carbon triple bond in the middle or atthe terminus of the C₂-C₆₀ alkyl group, and examples thereof include anethynyl group, and a propynyl group. The term “C₂-C₆₀ alkynylene group”as used herein refers to a divalent group having the same structure asthe C₂-C₆₀ alkynyl group.

The term “C₁-C₆₀ alkoxy group” as used herein refers to a monovalentgroup represented by —OA₁₀₁ (wherein A₁₀₁ represents the C₁-C₆₀ alkylgroup), and examples thereof include a methoxy group, an ethoxy group,and an isopropyloxy group.

The term “C₃-C₁₀ cycloalkyl group” as used herein refers to a monovalentsaturated hydrocarbon monocyclic group having 3 to 10 carbon atoms, andexamples thereof include a cyclopropyl group, a cyclobutyl group, acyclopentyl group, a cyclohexyl group, and a cycloheptyl group. The term“C₃-C₁₀ cycloalkylene group” as used herein refers to a divalent grouphaving the same structure as the C₃-C₁₀ cycloalkyl group.

The term “C₁-C₁₀ heterocycloalkyl group” as used herein refers to amonovalent monocyclic group having at least one heteroatom selected fromN, O, Si, P, and S as a ring-forming atom in addition to 1 to 10 carbonatoms, and examples thereof include a 1,2,3,4-oxatriazolidinyl group, atetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term“C₁-C₁₀ heterocycloalkylene group” as used herein refers to a divalentgroup having the same structure as the C₁-C₁₀ heterocycloalkyl group.

The term “C₃-C₁₀ cycloalkenyl group” as used herein refers to amonovalent monocyclic group that has 3 to 10 carbon atoms and at leastone carbon-carbon double bond in the ring thereof and no aromaticity,and examples thereof include a cyclopentenyl group, a cyclohexenylgroup, and a cycloheptenyl group. The term “C₃-C₁₀ cycloalkenylenegroup” as used herein refers to a divalent group having the samestructure as the C₃-C₁₀ cycloalkenyl group.

The term “C₁-C₁₀ heterocycloalkenyl group” as used herein refers to amonovalent monocyclic group that has at least one heteroatom selectedfrom N, O, Si, P, and S as a ring-forming atom in addition to 1 to 10carbon atoms, and at least one carbon-carbon double bond in its ring.Non-limiting examples of the C₁-C₁₀ heterocycloalkenyl group include a4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group, anda 2,3-dihydrothiophenyl group. The term “C₁-C₁₀ heterocycloalkenylenegroup” as used herein refers to a divalent group having the samestructure as the C₁-C₁₀ heterocycloalkenyl group.

The term “C₆-C₆₀ aryl group” as used herein refers to a monovalent grouphaving a carbocyclic aromatic system having 6 to 60 carbon atoms, andthe term “C₆-C₆₀ arylene group” as used herein refers to a divalentgroup having a carbocyclic aromatic system having 6 to 60 carbon atoms.Non-limiting examples of the C₆-C₆₀ aryl group include a phenyl group, anaphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenylgroup, and a chrysenyl group. When the C₆-C₆₀ aryl group and the C₆-C₆₀arylene group each include two or more rings, the rings may be fused toeach other.

The term “C₁-C₆₀ heteroaryl group” as used herein refers to a monovalentgroup having a carbocyclic aromatic system that has at least oneheteroatom selected from N, O, Si, P, and S as a ring-forming atom, inaddition to 1 to 60 carbon atoms. The term “C₁-C₆₀ heteroarylene group”as used herein refers to a divalent group having a carbocyclic aromaticsystem that has at least one heteroatom selected from N, O, Si, P, and Sas a ring-forming atom, in addition to 1 to 60 carbon atoms.Non-limiting examples of the C₁-C₆₀ heteroaryl group include a pyridinylgroup, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, atriazinyl group, a quinolinyl group, and an isoquinolinyl group. Whenthe C₁-C₆₀ heteroaryl group and the C₁-C₆₀ heteroarylene group eachinclude two or more rings, the rings may be condensed with each other.

The term “C₆-C₆₀ aryloxy group” as used herein indicates —OA₁₀₂ (whereinA₁₀₂ represents the C₆-C₆₀ aryl group), and the term “C₆-C₆₀ arylthiogroup” as used herein indicates —SA₁₀₃ (wherein A₁₀₃ represents theC₆-C₆₀ aryl group).

The term “monovalent non-aromatic condensed polycyclic group” as usedherein refers to a monovalent group (for example, having 8 to 60 carbonatoms) having two or more rings condensed with each other, only carbonatoms as ring-forming atoms, and no aromaticity in its entire molecularstructure. A non-limiting example of the monovalent non-aromaticcondensed polycyclic group is a fluorenyl group. The term “divalentnon-aromatic condensed polycyclic group” as used herein refers to adivalent group having the same structure as the monovalent non-aromaticcondensed polycyclic group.

The term “monovalent non-aromatic condensed heteropolycyclic group” asused herein refers to a monovalent group (for example, having 1 to 60carbon atoms) having two or more rings condensed to each other, at leastone heteroatom selected from N, O, Si, P, and S, other than carbonatoms, as a ring-forming atom, and no aromaticity in its entiremolecular structure. An example of the monovalent non-aromatic condensedheteropolycyclic group is a carbazolyl group. The term “divalentnon-aromatic condensed heteropolycyclic group” as used herein refers toa divalent group having the same structure as the monovalentnon-aromatic condensed heteropolycyclic group.

The term “C₅-C₆₀ carbocyclic group” as used herein refers to amonocyclic or polycyclic group having 5 to 60 carbon atoms in which aring-forming atom is carbon atoms only. The C₅-C₆₀ carbocyclic group maybe an aromatic carbocyclic group or a non-aromatic carbocyclic group.The C₅-C₆₀ carbocyclic group may be a ring, such as benzene, amonovalent group, such as a phenyl group, or a divalent group, such as aphenylene group. In one or more embodiments, depending on the number ofsubstituents connected to the C₅-C₆₀ carbocyclic group, the C₅-C₆₀carbocyclic group may be a trivalent group or a quadrivalent group.

The term “C₁-C₆₀ heterocyclic group” as used herein refers to a grouphaving the same structure as the C₁-C₆₀ carbocyclic group, except thatas a ring-forming atom, at least one heteroatom selected from N, O, Si,P, and S is used in addition to carbon (the number of carbon atoms maybe in a range of 1 to 60).

At least one substituent of the substituted C₅-C₆₀ carbocyclic group,the substituted C₁-C₆₀ heterocyclic group, the substituted C₃-C₁₀cycloalkylene group, the substituted C₁-C₁₀ heterocycloalkylene group,the substituted C₃-C₁₀ cycloalkenylene group, the substituted C₁-C₁₀heterocycloalkenylene group, the substituted C₆-C₆₀ arylene group, thesubstituted C₁-C₆₀ heteroarylene group, the substituted divalentnon-aromatic condensed polycyclic group, the substituted divalentnon-aromatic condensed heteropolycyclic group, the substituted C₁-C₆₀alkyl group, the substituted C₂-C₆₀ alkenyl group, the substitutedC₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxy group, thesubstituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substitutedmonovalent non-aromatic condensed polycyclic group, and the substitutedmonovalent non-aromatic condensed heteropolycyclic group may be selectedfrom:

deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitrogroup, an amidino group, a hydrazino group, a hydrazono group, a C₁-C₆₀alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, and aC₁-C₆₀ alkoxy group;

a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group,and a C₁-C₆₀ alkoxy group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂), —B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁),—S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂);

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group;

a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,and a monovalent non-aromatic condensed heteropolycyclic group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, —Si(Q₂₁)(Q₂₂)(Q₂₃),—N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂), —C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and—P(═O)(Q₂₁)(Q₂₂); and

—Si(Q₃₁)(Q₃₂)(Q₃₃), —N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁),—S(═O)₂(Q₃₁), and —P(═O)(Q₃₁)(Q₃₂), and

Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃ may each independently beselected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, acyano group, a nitro group, an amidino group, a hydrazino group, ahydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀ cycloalkyl group, aC₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₁-C₆₀ heteroarylgroup, a monovalent non-aromatic condensed polycyclic group, amonovalent non-aromatic condensed heteropolycyclic group, a biphenylgroup, and a terphenyl group.

The term “Ph” as used herein represents a phenyl group, the term “Me” asused herein represents a methyl group, the term “Et” as used hereinrepresents an ethyl group, the term “ter-Bu” or “Bu^(t),” as usedherein, represents a tert-butyl group, and the term “OMe” as used hereinrepresents a methoxy group.

The term “biphenyl group” as used herein refers to a “phenyl groupsubstituted with a phenyl group”. The “biphenyl group” is a “substitutedphenyl group” having a “0C₆-06₀ aryl group” as a substituent.

The term “terphenyl group” as used herein refers to a “phenyl groupsubstituted with a biphenyl group. The “terphenyl group” is a “phenylgroup” having, as a substituent, a “0C₆-C₆₀ aryl group substituted witha C₆-C₆₀ aryl group.”

* and *′ as used herein, unless defined otherwise, each refer to abinding site to a neighboring atom in a corresponding formula.

Hereinafter, a compound according to embodiments and an organiclight-emitting device according to embodiments will be described in moredetail with reference to Synthesis Examples and Examples. The expression“B was utilized instead of A” used in describing Synthesis Examples andExamples indicates that an identical number of molar equivalents of Bwas utilized in place of molar equivalents of A.

SYNTHESIS EXAMPLE Synthesis Example 1: Synthesis of Compound BD1

1) Synthesis of Intermediate 1-C

3.96 g (36.0 mmol) of 3-aminophenol, 6.54 g (30.0 mmol) of3-iodoaniline, 13.8 g (60.0 mmol) of potassium triphosphate, 1.14 g (6.0mmol) of iodine copper, and 0.74 g (6.0 mmol) of picolinic acid wereadded to a reaction container and suspended in 60 ml of dimethylsulfoxide. The reaction mixture was heated and stirred at a temperature85° C. for 24 hours. After the reaction was completed, the reactionproduct was cooled to room temperature, and 300 ml of distilled waterwas added thereto. Then, an organic layer was extracted therefromutilizing ethyl acetate. The extracted organic layer was washedutilizing a saturated sodium chloride aqueous solution and driedutilizing sodium sulfate. The solvent was removed therefrom, and aresidue obtained therefrom was separated by column chromatography toobtain 5.40 g of Intermediate 1-C, which is a transparent oil.

2) Synthesis of Intermediate 1-D

4.0 g (20.0 mmol) of the synthesized 3,3′-oxyaniline was dissolved in100 ml of acetone. An aqueous hydrochloric acid solution (21 ml ofhydrochloric acid was diluted with 30 ml of distilled water) was addeddropwise thereto. The reaction solution was cooled to a temperature of0° C., and 8.4 g (121.8 mmol) of sodium nitride was dissolved in 50 mlof distilled water and slowly added dropwise thereto. The solution wasstirred at a temperature of 0° C. for 1 hour, 25 g (150.6 mmol) ofpotassium iodide was dissolved in 50 ml of distilled water and addeddropwise thereto. The reaction mixture was stirred at a temperature of0° C. for 2 hours, heated to a temperature of 60° C., and additionallystirred for 4 hours.

Sodium bisulfite was added thereto to remove the residual iodine, andthe reaction mixture was concentrated under reduced pressure. Theresidue obtained therefrom was extracted utilizing dimethylchloride, andan organic layer was dried utilizing magnesium sulfate. Then, theproduct obtained therefrom was purified by column chromatography toobtain 6.0 g of Intermediate 1-D, which is a white solid.

3) Synthesis of Intermediate 1-E

5.6 g (13.3 mmol) of the synthesized 3,3′-oxybis(iodobenzene), 5.2 ml(36.8 mmol) of trimethylsilylacetylene, 0.94 g (1.34 mmol) ofPdCl₂(PPh₃)₂, 0.7 g (2.67 mmol) of triphenylphosphine, 0.38 g (2.00mmol) of iodine copper, and 80 ml of a mixed solvent oftetrahydrofuran/triethylamine (v/v=3:1) were added to a 250-ml reactioncontainer and stirred for 12 hours. After the reaction was completed,the reaction product was concentrated under reduced pressure, and anorganic layer was extracted therefrom utilizing an aqueous solution ofmethylene chloride and ammonium chloride. The organic layer was washedutilizing distilled water and brine. The organic layer was driedutilizing magnesium sulfate and purified by column chromatography(methylene chloride:n-hexane=1:9). The obtained white solid wasdissolved in 40 ml of tetrahydrofuran, and 1.0 M solution oftetrabutylammonium fluoride was added thereto and stirred for 12 hours.The reaction mixture was concentrated under reduced pressure, and theproduct was extracted therefrom utilizing methylene chloride. Theproduct was dried utilizing magnesium sulfate and purified bychromatography (methylene chloride:n-hexane=1:9) to obtain 2.55 g ofIntermediate 1-E that is a white solid.

4) Synthesis of Intermediate 1-F

0.4 g (1.83 mmol) of the synthesized 3,3′-oxybis(ethynylbenzene), 0.49 g(1.92 mmol) of 1,12-diazidodecane, 0.95 g (7.32 mmol) ofdisopropylamine, tris[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]amine (1mol %), and 240 ml of dichloromethane were added to a 500-ml reactioncontainer and bubbled with nitrogen gas for 30 minutes. [Cu(CH₃CN)₄]PF₆(1 mol %) was added as a catalyst and stirred at room temperature for 6days. The solvent was removed under reduced pressure, and the residueobtained therefrom was dissolved in dichloromethane and washed severaltimes with saturated ammonium chloride, distilled water, and saturatedsodium chloride aqueous solution. An organic layer was dried utilizingmagnesium sulfate, and the residue obtained therefrom was purified bycolumn chromatography (methylenechloride:ethyl acetate=5:1) to obtain0.2 g Intermediate 1-F.

5) Synthesis of Compound BD1

0.8 g of the synthesized ligand 1-F, 0.06 g of tetrabutylammoniumbromide, and 0.8 g of K₂PtCl₄ were added to a reaction container and 100ml of acetic acid was added thereto. The reaction mixture was stirred atroom temperature for 1 day and stirred at a temperature of 140° C. for 4days. 100 ml of distilled water was added thereto, and the resultingsolid was filtered under reduced pressure. The solid was dissolved inmethylene chloride and washed utilizing distilled water and saturatedsodium chloride. An organic layer was dried utilizing magnesium sulfateand purified by column chromatography utilizing methylene chloride toobtain Compound BD1.

Synthesis Example 2: Synthesis of Compound BD2

Compound BD2 was obtained in the same manner as in Synthesis Example 1,except that 3-amino-5-methylphenol was utilized instead of3-aminophenol, and 3-iodo-5-methylaniline was utilized instead of3-iodoaniline.

Synthesis Example 3: Synthesis of Compound BD3

Compound BD3 was obtained in the same manner as in Synthesis Example 1,except that 3-Amino-5-tert-butylphenol was utilized instead of3-aminophenol, and 3-iodo-5-tertiarybutylaniline was utilized instead of3-iodoaniline.

Synthesis Example 4: Synthesis of Compound BD4

Compound BD4 was obtained in the same manner as in Synthesis Example 1,except that 3-amino-5-trimethylsilylphenol was utilized instead of3-aminophenol, and 3-iodo-5-trimethylsilyl aniline was utilized insteadof 3-iodoaniline.

Synthesis Example 5: Synthesis of Compound BD5

Compound BD5 was obtained in the same manner as in Synthesis Example 1,except that 3-amino-5-fluorophenol was utilized instead of3-aminophenol, and 3-fluoro-5-iodoaniline was utilized instead of3-iodoaniline.

Synthesis Example 6: Synthesis of Compound BD12

Compound BD12 was obtained in the same manner as in Synthesis Example 1,except that 1-azido-2-(2-(2-(2-azidoethoxy)ethoxy)ethoxy)ethane wasutilized instead of 1,12-diazidodecane.

Synthesis Example 7: Synthesis of Compound BH2

1) Synthesis of Intermediate 2-A

15 g (89.7 mmol) of carbazole, 38 g (179.4 mmol) of potassium phosphate,and 20 ml (179.4 mmol) of 1-bromo-2-fluorobenzene were suspended in 300ml of dimethylformamide, heated to a temperature of 160° C., and stirredfor 12 hours. Distilled water and methylene chloride were added to thereaction mixture and washed several times utilizing saturated sodiumchloride. The product obtained therefrom was dried utilizing magnesiumsulfate and purified by column chromatography(dichloromethane:n-hexane=5:95) to obtain 23 g of Intermediate 2-A.

2) Synthesis of Compound BH2

0.50 g (1.55 mmol) of synthesized Intermediate [2-A], 0.53 g (1.85 mmol)of 2-((9H-carbazole-9-yl)phenyl)boronic acid, 0.26 g (1.85 mmol) ofpotassium carbonate, and 4 mol % of tetrakistriphenylphosphine palladiumcatalyst were suspended in 10 ml of a mixed solvent of toluene andethanol (4:1), heated to a temperature of 120° C., and stirred for 12hours. Distilled water and dimethylchloride were added to the reactionmixture, and the product obtained therefrom was extracted therefrom anddried utilizing magnesium sulfate and purified by column chromatographyto obtain 0.5 g of Compound BH2.

Synthesis Example 8: Synthesis of Compound BH15

1) Synthesis of Intermediate 3-A

15 g (63.59 mmol) of 1,4-dibromobenzene was dissolved in 200 ml oftetrahydrofuran and cooled to a temperature of −78° C. 25 ml (63.59mmol) of 2.5 M solution of n-butyllithium was added thereto and stirredfor 1 hour. 11.5 g (63.59 mmol) of 9-fluorenone was dissolved in 50 mlof tetrahydrofuran and added dropwise to the reaction mixture. Thereaction mixture was heated and stirred at room temperature for 12hours, and distilled water and ethyl acetate were added thereto. Theproduct was extracted therefrom and washed several times utilizingsaturated sodium chloride. The product was dried utilizing magnesiumsulfate and purified by column chromatography (dichloromethane:n-hexane=1:4) to obtain 19 g of Intermediate 3-A.

2) Synthesis of Intermediate 3-B

15.7 g (64.58 mmol) of the synthesized Intermediate 3-A and 15.6 g(64.58 mmol) of phenylcarbazole were dissolved in 350 ml of methylenechloride and cooled to a temperature of 0° C., and 1.5 ml of Eaton'sreagent was added dropwise thereto and stirred for 1 hour. Distilledwater and ethyl acetate were added thereto, and the product wasextracted therefrom and washed several times utilizing saturated sodiumchloride. The product obtained therefrom was dried utilizing magnesiumsulfate and purified by column chromatography(dichloromethane:n-hexane=1:9) to obtain 13.8 g of Intermediate 3-B.

3) Synthesis of Intermediate 3-C

13.8 g (24.5 mmol) of the synthesized Intermediate 3-B was dissolved in150 ml of tetrahydrofuran and cooled to a temperature of −78° C., and12.8 ml of 2.5 M solution of n-butyllithium was added thereto andstirred for 2 hour. 6.5 ml of diphenylphosphine chloride was addeddropwise thereto and heated and stirred at room temperature for 12hours. Distilled water and ethyl acetate were added thereto, and aproduct was extracted therefrom and washed several times utilizingsaturated sodium chloride. The product obtained therefrom was driedutilizing magnesium sulfate and purified by column chromatography(dichloromethane:ethylacetate=1:9) to obtain Intermediate 3-C.

4) Synthesis of Compound BH15

The synthesized Intermediate 3-C was dissolved in 300 ml ofdimethylchloride and 60 ml of hydrogen peroxide was added thereto andstirred for 30 minutes. Distilled water was added thereto, and a productwas extracted therefrom and washed several times utilizing saturatedsodium hydrogen carbonate aqueous solution. The product obtainedtherefrom was dried utilizing magnesium sulfate and purified by columnchromatography (dichloromethane:ethylacetate=1:9) to obtain 7.7 g ofCompound BH15.

Synthesis Example 9: Synthesis of Compound BH4

1) Synthesis of Intermediate 4-A

5.9 g (23.79 mmol) of 2-bromodibenzofuran, carbazole (23.79 mmol), 1.14g (0.3 mol %) of iodine copper, 1.3 g (0.3 mol %) of1,10-phenanthroline, and 6.6 g (47.58 mmol) of potassium carbonate weresuspended in 120 ml of dimethylformanide. The reaction mixture washeated and stirred under reflux for 24 hours. The reaction mixture wascooled to room temperature, and the reaction mixture was added dropwiseto distilled water and solidified. The solid obtained therefrom wasfiltered and dried. The dried solid was purified by columnchromatography (methylene chloride:n-hexane=1:9) to obtain 8.0 g ofIntermediate 4-A.

2) Synthesis of Compound BH4

8 g (16.50 mmol) of the synthesized Intermediate 4-A was dissolved in 80ml of tetrahydrofuran and cooled to a temperature of −78° C., and 8 ml(19.80 mmol) of 2.5 M solution of n-butyllithium was added thereto andstirred for 1 hour. 5.84 g (19.80 mmol) of triphenylsilyl chloride wasdissolved in 20 ml of tetrahydrofuran and added dropwise to the reactionmixture. The reaction mixture was heated and stirred at room temperaturefor 12 hours, and distilled water and ethyl acetate were added theretoto extract the product. The product was dried utilizing magnesiumsulfate and purified by column chromatography(dichloromethane:n-hexane=1:4) to obtain 9.3 g of Compound BH4.

EXAMPLES Example 1

As a substrate and an ITO anode, a glass substrate, on which a Corning15 O/cm² (1,200 Å) ITO was formed, was cut into a size of 50 mm×50mm×0.7 mm, sonicated with isopropyl alcohol and pure water each for 5minutes, and then cleaned by exposure to ultraviolet rays and ozone for30 minutes. Then, the glass substrate was provided to a vacuumdeposition apparatus.

2-TNATA was vacuum-deposited on the ITO anode formed on the glasssubstrate to form a hole injection layer having a thickness of 600 Å,and NPB was vacuum-deposited on the hole injection layer to form a holetransport layer having a thickness of 300 Å.

Compound BH1 (host) and Compound BD1 (dopant) were co-deposited on thehole transport layer at a host-to-dopant weight ratio of 90:10 to forman emission layer having a thickness of 300 Å.

TSP01 was deposited on the emission layer to form a hole blocking layerhaving a thickness of 50 Å, Alq₃ was deposited on the hole blockinglayer to form an electron transport layer having a thickness of 300 Å,LiF was deposited on the electron transport layer to form an electroninjection layer having a thickness of 10 Å, and Al was vacuum-depositedon the electron injection layer to form a cathode having a thickness of3,000 Å, thereby completing the manufacture of an organic light-emittingdevice.

Examples 2 to 9

Organic light-emitting devices were manufactured in the same manner asin Example 1, except that Compounds shown in Table 1 were each utilizedin forming an emission layer instead of Compound BD1 (dopant) andCompound BH1 (host) utilized in Example 1.

Example 11

As an anode, a glass substrate, on which a Corning 15 Ω/cm² (1,200 Å)ITO was formed, was cut into a size of 50 mm×50 mm×0.7 mm, sonicatedwith isopropyl alcohol and pure water each for 5 minutes, and thencleaned by exposure to ultraviolet rays and ozone for 30 minutes. Then,the glass substrate was provided to a vacuum deposition apparatus. KnownCompound 2-TNATA was vacuum-deposited on the glass substrate to form ahole injection layer having a thickness of 600 Å, and NPB as a holetransport compound was vacuum-deposited to form a hole transport layerhaving a thickness of 300 Å. Compound BD1 for a blue fluorescentemission layer was co-deposited on the hole transport layer with a mixedhost having a dopant ratio of 10% and an ETH1:BH1 weight ratio of 1:9 toform an emission layer having a thickness of 300 Å. Then, ETH1 wasvacuum-deposited to form a hole blocking layer having a thickness of 50Å. Alq₃ was deposited on the emission layer (e.g., deposited on the holeblocking layer which was deposited on the emission layer) to form anelectron transport layer having a thickness of 300 Å. LiF, which is analkali metal halide, was deposited on the electron transport layer toform an electron injection layer having a thickness of 10 Å, and Al wasvacuum-deposited to form a cathode electrode having a thickness of 3,000Å and to form an LiF/AI electrode, thereby completing the manufacture ofan organic light-emitting device.

Example 12

An organic light-emitting device was manufactured in the same manner asin Example 11, except that ETH2 was utilized instead of ETH1 as a host.

Comparative Example 1

As a substrate and an ITO anode, a glass substrate, on which a Corning150/cm² (1,200 Å) ITO was formed, was cut into a size of 50 mm×50 mm×0.7mm, sonicated with isopropyl alcohol and pure water each for 5 minutes,and then cleaned by exposure to ultraviolet rays and ozone for 30minutes. Then, the glass substrate was provided to a vacuum depositionapparatus.

NPB was vacuum-deposited on the ITO anode formed on the glass substrateto form a hole transport layer having a thickness of 300 Å. mCP wasdeposited on the hole transport layer to form an electron blocking layerhaving a thickness of 60 Å. BCPO (host) and Compound BD1 (dopant) wereco-deposited on the electron blocking layer at a host-to-dopant weightratio of 90:10 to form an emission layer having a thickness of 300 Å.

DPEPO was deposited on the emission layer to form a hole blocking layerhaving a thickness of 50 Å, Alq₃ was deposited on the hole blockinglayer to form an electron transport layer having a thickness of 300 Å,LiF was deposited on the electron transport layer to form an electroninjection layer having a thickness of 10 Å, and Al was vacuum-depositedon the electron injection layer to form a cathode having a thickness of3,000 Å, thereby completing the manufacture of an organic light-emittingdevice.

Comparative Examples 2 to 4

Organic light-emitting devices were manufactured in the same manner asin Example 1, except that Compounds shown in Table 1 were each utilizedto form an emission layer instead of Compound BD1 utilized in Example 1.

Evaluation Example 1

The driving voltage, current density, luminance, luminescent efficiency,and maximum emission wavelength of the organic light-emitting devicesmanufactured according to Examples 1 to 12 and Comparative Examples 1 to4 were measured utilizing Keithley SMU 236 and a luminance meter PR650,and results thereof are shown in Table 1.

TABLE 1 Maximum Driving Current Luminescent emission Dopant Host voltagedensity Luminance efficiency wavelength Lifespan compound compound (V)(mA/cm²) (cd/m²) (cd/A) (nm) (T90, h) Example 1 BD1 BH1 4.9 6.5 100020.1 453 7.0 Example 2 BD2 BH1 4.7 6.4 1000 17.2 457 3.0 Example 3 BD3BH2 4.3 6.4 1000 15.1 457 11.0 Example 4 BD4 BH2 4.3 5.8 1000 16.2 45711.1 Example 5 BD5 BH4 4.3 5.6 1000 16.7 456 15.4 Example 6 BD6 BH4 4.35.1 1000 15.3 457 5.5 Example 7 BD11 BH4 4.4 5.5 1000 19.2 457 4.5Example 8 BD16 BH22 4.4 5.6 1000 18.4 455 7.8 Example 9 BD17 BH25 4.35.2 1000 16.9 456 9.1 Example 11 BD1 BH1, 4.4 5.2 1000 16.2 457 21.0ETH1 Example 12 BD1 BH1, 4.4 5.2 1000 16.5 455 24.0 ETH2 Comparative BD1BCPO 5.5 14.2 1000 6.6 451 0.3 Example 1 Comparative A BH1 5.2 9.9 10006.5 488 0.1 Example 2 Comparative B BH1 5.2 9.3 1000 10.7 478 0.1Example 3 Comparative C BH1 5.7 8.8 1000 8.2 478 0.1 Example 4

Referring to Table 1, it is confirmed that the organic light-emittingdevices of Examples 1 to 8, 11, and 12 have a low driving voltage, highluminescent efficiency, and excellent lifespan, as compared with theorganic light-emitting devices of Comparative Examples 1 to 4.

The organic light-emitting device may have a low driving voltage, a highefficiency, and a long lifespan.

It should be understood that embodiments described herein should beconsidered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each embodimentshould typically be considered as available for other similar featuresor aspects in other embodiments.

While one or more embodiments have been described with reference to thedrawing, it will be understood by those of ordinary skill in the artthat various changes in form and details may be made therein withoutdeparting from the spirit and scope as defined by the following claims,and equivalents thereof.

What is claimed is:
 1. An organic light-emitting device comprising: afirst electrode; a second electrode facing the first electrode; and anorganic layer between the first electrode and the second electrode andcomprising an emission layer, wherein the organic layer furthercomprises a first compound represented by Formula 1 and a secondcompound represented by Formula 2:

wherein, in Formulae 1, 1-1, 1-2, and 1-3, CY₁ and CY₂ are eachindependently a group represented by one of Formulae 1-1, 1-2, and 1-3,m1 and m2 are each independently 0, 1 or 2, wherein a sum of m1 and m2is 2, L₁ and L₂ are each independently selected from a substituted orunsubstituted C₃-C₁₀ cycloalkylene group, a substituted or unsubstitutedC₁-C₁₀ heterocycloalkylene group, a substituted or unsubstituted C₃-C₁₀cycloalkenylene group, a substituted or unsubstituted C₁-C₁₀heterocycloalkenylene group, a substituted or unsubstituted C₆-C₆₀arylene group, a substituted or unsubstituted C₁-C₆₀ heteroarylenegroup, a substituted or unsubstituted divalent non-aromatic condensedpolycyclic group, a substituted or unsubstituted divalent non-aromaticcondensed heteropolycyclic group, and —Si(Q₁)(Q₂)-, b1 is an integerfrom 0 to 5, b2 is an integer from 0 to 5, X₁ to X₄ are eachindependently selected from a single bond, *—O—*, *—S—*, *—C(R₈)(R₉)—*′,*—C(═O)—*′, *—B(R₈)(R₉)—*′, *—N(R₈)—*′, *—P(R₈)—*′, and *—Si(R₈)(R₉)—*′,rings A₁ to A₆ are each independently a C₅-C₆₀ carbocyclic group or aC₂-C₆₀ heterocyclic group, R₁ to R₉ are each independently selected fromhydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid group or a salt thereof, a sulfonicacid group or a salt thereof, a phosphoric acid group or a salt thereof,a substituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₁₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted monovalent non-aromatic condensed polycyclic group, asubstituted or unsubstituted monovalent non-aromatic condensedheteropolycyclic group, —Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —N(Q₁)(Q₂),—P(Q₁)(Q₂), —C(═O)(Q₁), —S(═O)(Q₁), —S(═O)₂(Q₁), —P(═O)(Q₁)(Q₂), and—P(═S)(Q₁)(Q₂), a1 to a7 are each independently an integer from 1 to 8,in Formula 2, M₁₁ is selected from platinum (Pt), palladium (Pd), copper(Cu), silver (Ag), gold (Au), rhodium (Rh), iridium (Ir), ruthenium(Ru), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium(Eu), terbium (Tb), and thulium (Tm), A₁₁ to A₁₄ are each independentlyselected from a C₅-C₆₀ carbocyclic group and a C₁-C₆₀ heterocyclicgroup, Y₁₁ to Y₁₄ are each independently N or C, T₁₁ to T₁₄ are eachindependently selected from a single bond, O, and S, L₁₁ to L₁₃ are eachindependently selected from a single bond, *—O—*′, *—S—*′,*—C(R₁₅)(R₁₆)—*′, *—C(R₁₅)═*′, *═C(R₁₅)—*′, *—C(R₁₅)═C(R₁₆)—*′,*—C(═O)—*′, *—C(═S)—*′, *—C═C—*′, *—B(R₁₅)—*′, *—N(R₁₅)—*′, *—P(R₁₅)—*′,*—Si(R₁₅)(R₁₆)—*′, *—P(═O)(R₁₅)(R₁₆)—*′, and *—Ge(R₁₅)(R₁₆)—*′, b11 tob13 are each independently an integer from 0 to 3, when b11 is 0, A₁₁and A₁₂ are not linked to each other, when b12 is 0, A₁₂ and A₁₃ are notlinked to each other, and when b13 is 0, A₁₃ and A₁₄ are not linked toeach other, L₁₄ to L₁₆ are each independently selected from *—O—*′,*—S—*′, *—C(═O)—*′, *—C(═S)—*′, *—B(R₁₇)—*′, *—N(R₁₇)—*′, *—P(R₁₇)—*′,*—Si(R₁₇)(R₁₈)—*′, *—P(═O)(R₁₇)(R₁₈)—*′, *—Ge(R₁₇)(R₁₈)—*′, a divalentC₂-C₂₀ hydrocarbon group, a divalent C₅-C₆₀ carbocyclic group, and adivalent C₁-C₆₀ heterocyclic group, b14 and b15 are each independentlyan integer from 1 to 5, b16 is an integer from 0 to 5, when b16 is 0,L₁₆ is a single bond, R₁₁ to R₁₈ are each independently selected fromhydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group,a nitro group, an amidino group, a hydrazino group, a hydrazono group, asubstituted or unsubstituted C₁-C₆₀ alkyl group, a substituted orunsubstituted C₂-C₆₀ alkenyl group, a substituted or unsubstitutedC₂-C₆₀ alkynyl group, a substituted or unsubstituted C₁-C₆₀ alkoxygroup, a substituted or unsubstituted C₃-C₁₀ cycloalkyl group, asubstituted or unsubstituted C₁-C₁₀ heterocycloalkyl group, asubstituted or unsubstituted C₃-C₀₀ cycloalkenyl group, a substituted orunsubstituted C₁-C₁₀ heterocycloalkenyl group, a substituted orunsubstituted C₆-C₆₀ aryl group, a substituted or unsubstituted C₆-C₆₀aryloxy group, a substituted or unsubstituted C₆-C₆₀ arylthio group, asubstituted or unsubstituted C₁-C₆₀ heteroaryl group, a substituted orunsubstituted C₁-C₆₀ heteroaryloxy group, a substituted or unsubstitutedC₁-C₆₀ heteroarylthio group, a substituted or unsubstituted monovalentnon-aromatic condensed polycyclic group, a substituted or unsubstitutedmonovalent non-aromatic condensed heteropolycyclic group,—Si(Q₁)(Q₂)(Q₃), —B(Q₁)(Q₂), —N(Q₁)(Q₂), —P(Q₁)(Q₂), —C(═O)(Q₁),—S(═O)(Q₁), —S(═O)₂(Q₁), —P(═O)(Q₁)(Q₂), and —P(═S)(Q₁)(Q₂), R₁₅ andR₁₁; R₁₅ and R₁₂; R₁₅ and R₁₃; or R₁₅ and R₁₄ are optionally linked toform a substituted or unsubstituted C₅-C₆₀ carbocyclic group or asubstituted or unsubstituted C₁-C₆₀ heterocyclic group, a11 to a14 areeach independently an integer from 1 to 8, * and *′ each indicate abinding site to a neighboring atom, at least one substituent of thesubstituted C₃-C₁₀ cycloalkylene group, the substituted C₁-C₁₀heterocycloalkylene group, the substituted C₃-C₀₀ cycloalkenylene group,the substituted C₁-C₁₀ heterocycloalkenylene group, the substitutedC₆-C₆₀ arylene group, the substituted C₁-C₆₀ heteroarylene group, thesubstituted divalent non-aromatic condensed polycyclic group, thesubstituted divalent non-aromatic condensed heteropolycyclic group, thesubstituted C₁-C₆₀ alkyl group, the substituted C₂-C₆₀ alkenyl group,the substituted C₂-C₆₀ alkynyl group, the substituted C₁-C₆₀ alkoxygroup, the substituted C₃-C₁₀ cycloalkyl group, the substituted C₁-C₁₀heterocycloalkyl group, the substituted C₃-C₁₀ cycloalkenyl group, thesubstituted C₁-C₁₀ heterocycloalkenyl group, the substituted C₆-C₆₀ arylgroup, the substituted C₆-C₆₀ aryloxy group, the substituted C₆-C₆₀arylthio group, the substituted C₁-C₆₀ heteroaryl group, the substitutedmonovalent non-aromatic condensed polycyclic group, and the substitutedmonovalent non-aromatic condensed heteropolycyclic group is selectedfrom: deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amidino group, a hydrazino group, a hydrazono group, aC₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, anda C₁-C₆₀ alkoxy group; a C₁-C₆₀ alkyl group, a C₂-C₆₀ alkenyl group, aC₂-C₆₀ alkynyl group, and a C₁-C₆₀ alkoxy group, each substituted withat least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxylgroup, a cyano group, a nitro group, an amidino group, a hydrazinogroup, a hydrazono group, a C₃-C₀₀ cycloalkyl group, a C₁-C₁₀heterocycloalkyl group, a C₃-C₁₀ cycloalkenyl group, a C₁-C₁₀heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, aC₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, a monovalentnon-aromatic condensed polycyclic group, a monovalent non-aromaticcondensed heteropolycyclic group, —Si(Q₁₁)(Q₁₂)(Q₁₃), —N(Q₁₁)(Q₁₂),—B(Q₁₁)(Q₁₂), —C(═O)(Q₁₁), —S(═O)₂(Q₁₁), and —P(═O)(Q₁₁)(Q₁₂); a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₀₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀ heteroaryl group, amonovalent non-aromatic condensed polycyclic group, a monovalentnon-aromatic condensed heteropolycyclic group, a biphenyl group, and aterphenyl group; a C₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkylgroup, a C₃-C₀₀ cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, aC₆-C₆₀ aryl group, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, aC₁-C₆₀ heteroaryl group, a monovalent non-aromatic condensed polycyclicgroup, and a monovalent non-aromatic condensed heteropolycyclic group,each substituted with at least one selected from deuterium, —F, —Cl,—Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidinogroup, a hydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, aC₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, aC₃-C₁₀ cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀cycloalkenyl group, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ arylgroup, a C₆-C₆₀ aryloxy group, a C₆-C₆₀ arylthio group, a C₁-C₆₀heteroaryl group, a monovalent non-aromatic condensed polycyclic group,a monovalent non-aromatic condensed heteropolycyclic group excluding acarbazolyl group, —Si(Q₂₁)(Q₂₂)(Q₂₃), —N(Q₂₁)(Q₂₂), —B(Q₂₁)(Q₂₂),—C(═O)(Q₂₁), —S(═O)₂(Q₂₁), and —P(═O)(Q₂₁)(Q₂₂); and —Si(Q₃₁)(Q₃₂)(Q₃₃),—N(Q₃₁)(Q₃₂), —B(Q₃₁)(Q₃₂), —C(═O)(Q₃₁), —S(═O)₂(Q₃₁), and—P(═O)(Q₃₁)(Q₃₂), and Q₁ to Q₃, Q₁₁ to Q₁₃, Q₂₁ to Q₂₃, and Q₃₁ to Q₃₃are each independently selected from hydrogen, deuterium, —F, —Cl, —Br,—I, a hydroxyl group, a cyano group, a nitro group, an amidino group, ahydrazino group, a hydrazono group, a C₁-C₆₀ alkyl group, a C₂-C₆₀alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxy group, a C₃-C₁₀cycloalkyl group, a C₁-C₁₀ heterocycloalkyl group, a C₃-C₁₀ cycloalkenylgroup, a C₁-C₁₀ heterocycloalkenyl group, a C₆-C₆₀ aryl group, a C₆-C₆₀aryl group substituted with a C₁-C₆₀ alkyl group, a C₆-C₆₀ aryl groupsubstituted with a C₆-C₆₀ aryl group, a terphenyl group, a C₁-C₆₀heteroaryl group, a C₁-C₆₀ heteroaryl group substituted with a C₁-C₆₀alkyl group, a C₁-C₆₀ heteroaryl group substituted with a C₆-C₆₀ arylgroup, a monovalent non-aromatic condensed polycyclic group, and amonovalent non-aromatic condensed heteropolycyclic group.
 2. The organiclight-emitting device of claim 1, wherein L₁ and L₂ in Formulae 1, 1-1,1-2, and 1-3 are each independently selected from: a phenylene group, anaphthylene group, a fluorenylene group, a spiro-fluorenylene group, abenzofluorene group, a dibenzofluorene group, a phenanthrenylene group,an anthracenylene group, a pyrenylene group, a chrysenylene group, apyridinylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a quinolinylene group, an isoquinolinylene group,a quinoxalinylene group, a quinazolinylene group, a carbazolylene group,and a triazinylene group; a phenylene group, a naphthylene group, afluorenylene group, a spiro-fluorenylene group, a benzofluorenylenegroup, a dibenzofluorenylene group, a phenanthrenylene group, ananthracenylene group, a pyrenylene group, a chrysenylene group, apyridinylene group, a pyrazinylene group, a pyrimidinylene group, apyridazinylene group, a quinolinylene group, an isoquinolinylene group,a quinoxalinylene group, a quinazolinylene group, a carbazolylene group,and a triazinylene group, each substituted with at least one selectedfrom deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, anitro group, an amino group, an amidino group, a hydrazine group, ahydrazone group, a carboxylic acid group or a salt thereof, a sulfonicacid group or a salt thereof, a phosphoric acid group or a salt thereof,a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenylgroup, a terphenyl group, a naphthyl group, a fluorenyl group, aspiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group,a phenanthrenyl group, an anthracenyl group, a pyrenyl group, achrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, an isoindolyl group, a quinolinyl group, anisoquinolinyl group, a quinoxalinyl group, a quinazolinyl group, acarbazolyl group, and a triazinyl group; and —Si(Q₄)(Q₅)-, and Q₄ and Q₅are each independently selected from: a C₁-C₁₀ alkyl group, a C₁-C₁₀alkoxy group, and a phenyl group; and a phenyl group, a biphenyl group,a terphenyl group, and a naphthyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, a C₁-C₂₀ alkyl group, a C₁-C₂₀ alkoxy group, aphenyl group, a biphenyl group, a terphenyl group, and a naphthyl group.3. The organic light-emitting device of claim 1, wherein A₁ to A₆ inFormulae 1-1, 1-2, and 1-3 are each independently selected from abenzene ring, a naphthalene ring, a pyridine ring, a pyrimidine ring, apyrazine ring, a pyridazine ring, a triazine ring, a quinoline ring, anisoquinoline ring, a quinoxaline ring, a quinazoline ring, and a ringrepresented by Formula 4:

wherein, in Formula 4, X₅ and X₆ are each independently selected from*—O—*, *—S—*, *—C(R₈)(R₉)*′, *—C(═O)—*′, *—B(R₈)(R₉)—*′, *—N(R₈)—*′,*—P(R₈)—*′, and *—Si(R₈)(R₉)—*′, and R₈ and R₉ are the same as describedin connection with Formulae 1, 1-1, 1-2, and 1-3.
 4. The organiclight-emitting device of claim 1, wherein R₁ to R₉ in Formulae 1-1, 1-2and 1-3 are each independently selected from: hydrogen, deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₁-C₆₀ alkylgroup, a C₂-C₆₀ alkenyl group, a C₂-C₆₀ alkynyl group, a C₁-C₆₀ alkoxygroup, a phenyl group, a naphthyl group, a fluorenyl group, a pyrenylgroup, a phenalenyl group, a phenanthrenyl group, an anthracenyl group,a fluoranthenyl group, a triphenylenyl group, a pyrazolyl group, animidazolyl group, a benzimidazolyl group, a pyridinyl group, a pyrimidylgroup, a quinolinyl group, an isoquinolinyl group, a benzoquinolinylgroup, a naphthyridinyl group, a quinoxalinyl group, a quinazolinylgroup, a carbazolyl group, a phenanthridinyl group, an acridinyl group,a phenanthrolinyl group, a phenazinyl group, a triazinyl group, adibenzofuranyl group, a dibenzothiophenyl group, a biphenyl group, and aterphenyl group; a phenyl group, a naphthyl group, a fluorenyl group, apyrenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenylgroup, a fluoranthenyl group, a triphenylenyl group, a pyrazolyl group,an imidazolyl group, a benzimidazolyl group, a pyridinyl group, apyrimidyl group, a quinolinyl group, an isoquinolinyl group, abenzoquinolinyl group, a naphthyridinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, a phenanthridinyl group, anacridinyl group, a phenanthrolinyl group, a phenazinyl group, atriazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group, each substituted with at leastone selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyanogroup, a nitro group, a methyl group, an ethyl group, a propyl group, anisobutyl group, a sec-butyl group, ter-butyl group, pentyl group, anisoamyl group, a hexyl group, a C₁-C₆₀ alkoxy group, a cyclopentylgroup, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, acyclohexenyl group, a phenyl group, a naphthyl group, a fluorenyl group,a pyrenyl group, a phenalenyl group, a phenanthrenyl group, ananthracenyl group, a fluoranthenyl group, a triphenylenyl group, apyrazolyl group, an imidazolyl group, a benzimidazolyl group, apyridinyl group, a pyrimidyl group, a quinolinyl group, an isoquinolinylgroup, a benzoquinolinyl group, a naphthyridinyl group, a quinoxalinylgroup, a quinazolinyl group, a carbazolyl group, a phenanthridinylgroup, an acridinyl group, a phenanthrolinyl group, a phenazinyl group,a triazinyl group, a dibenzofuranyl group, a dibenzothiophenyl group, abiphenyl group, and a terphenyl group; and —Si(Q₄)(Q₅)(Q₆) and—P(═O)(Q₄)(Q₅), and Q₄ to Q₆ are each independently selected from: aC₁-C₁₀ alkyl group, a C₁-C₁₀ alkoxy group, and a phenyl group; and aphenyl group, a biphenyl group, a terphenyl group, and a naphthyl group,each substituted with at least one selected from deuterium, —F, —Cl,—Br, —I, a hydroxyl group, a cyano group, a nitro group, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, and a naphthyl group.
 5. The organic light-emittingdevice of claim 1, wherein the first compound is a compound representedby one of Formulae 1 Å, 1B, and 1C:

wherein, in Formulae 1 Å, 1B, and 1C, X₁ to X₄, A₁ to A₆, L₁, L₂, b2, R₁to R₇, and a1 to a7 are the same as described in connection withFormulae 1, 1-1, 1-2, and 1-3, X₃₁ and X₃₂ are each independently thesame as described in connection with X₃ in Formulae 1, 1-1, 1-2, and1-3, A₃₁ and A₃₂ are each independently the same as described inconnection with A₃ in Formulae 1, 1-1, 1-2, and 1-3, A₄₁ and A₄₂ areeach independently the same as described in connection with A₄ inFormulae 1, 1-1, 1-2, and 1-3, R₃₁ and R₃₂ are each independently thesame as described in connection with R₃ in Formulae 1, 1-1, 1-2, and1-3, R₄₁ and R₄₂ are each independently the same as described inconnection with R₄ in Formulae 1, 1-1, 1-2, and 1-3, a31 and a32 areeach independently the same as described in connection with a3 inFormulae 1, 1-1, 1-2, and 1-3, and a41 and a42 are each independentlythe same as described in connection with a4 in Formulae 1, 1-1, 1-2, and1-3.
 6. The organic light-emitting device of claim 1, wherein the firstcompound is selected from Compounds BH1 to BH28:


7. The organic light-emitting device of claim 1, wherein M₁₁ in Formula2 is selected from Pt, Pd, Cu, Ag, and Au.
 8. The organic light-emittingdevice of claim 1, wherein A₁₁ to A₁₄ in Formula 2 are eachindependently represented by one selected from Formulae 2-1 to 2-43:

wherein, in Formulae 2-1 to 2-43, X₂₁ to X₂₃ are each independentlyselected from C(R₂₄) and C—*, wherein at least two of X₂₁ to X₂₃ areeach C—*, X₂₄ is N—*, and X₂₅ and X₂₆ are each independently selectedfrom C(R₂₄) and C—*, wherein at least one of X₂₅ and X₂₆ is C—*, X₂₇ andX₂₈ are each independently selected from N, N(R₂₅), and N—*, and X₂₉ isselected from C(R₂₄) and C—*, wherein i) at least one of X₂₇ and X₂₈ isN—* and X₂₉ is C—*, or ii) X₂₇ and X₂₈ are each N—* and X₂₉ is C(R₂₄),R₂₁ to R₂₅ are each independently the same as described in connectionwith R₁₁ in Formula 1, b21 is selected from 1, 2, and 3, b22 is selectedfrom 1, 2, 3, 4, and 5, b23 is selected from 1, 2, 3, and 4, b24 isselected from 1 and 2, and indicates a binding site to a neighboringatom.
 9. The organic light-emitting device of claim 1, wherein, inFormula 2, Y₁₁, Y₁₂, and Y₁₃ are each C, and Y₁₄ is N; Y₁₁, Y₁₂, and Y₁₄are each C, and Y₁₃ is N; Y₁₁, Y₁₃, and Y₁₄ are each C, and Y₁₂ is N;Y₁₂, Y₁₃, and Y₁₄ are each C, and Y₁₁ is N; Y₁₁ and Y₁₄ are each C, andY₁₂ and Y₁₃ are each N; Y₁₁ and Y₁₄ are each N, and Y₁₂ and Y₁₃ are eachC; Y₁₁ and Y₁₂ are each C, and Y₁₃ and Y₁₄ are each N; Y₁₁ and Y₁₂ areeach N, and Y₁₃ and Y₁₄ are each C; Y₁₁ and Y₁₃ are each C, and Y₁₂ andY₁₄ are each N; or Y₁₁ and Y₁₃ are each N, and Y₁₂ and Y₁₄ are each C.10. The organic light-emitting device of claim 1, wherein, in Formula 2,L₁₄ and L₁₅ are each independently selected from *—O—*′, *—S—*′,*—N(R₁₉)—*′, a C₂-C₂₀ alkylene group, a C₂-C₂₀ alkenylene group, and aC₂-C₂₀ alkynylene group, R₁₉ is selected from: a phenyl group, abiphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group,a spiro-fluorenyl group, a benzofluorenyl group, a dibenzofluorenylgroup, a phenanthrenyl group, an anthracenyl group, a pyrenyl group, achrysenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinylgroup, a pyridazinyl group, a quinolinyl group, an isoquinolinyl group,a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and atriazinyl group; and a phenyl group, a biphenyl group, a terphenylgroup, a naphthyl group, a fluorenyl group, a spiro-fluorenyl group, abenzofluorenyl group, a dibenzofluorenyl group, a phenanthrenyl group,an anthracenyl group, a pyrenyl group, a chrysenyl group, a pyridinylgroup, a pyrazinyl group, a pyrimidinyl group, a pyridazinyl group, aquinolinyl group, an isoquinolinyl group, a quinoxalinyl group, aquinazolinyl group, a carbazolyl group, and a triazinyl group, eachsubstituted with at least one selected from deuterium, —F, —Cl, —Br, —I,a hydroxyl group, a cyano group, a nitro group, an amino group, anamidino group, a hydrazine group, a hydrazone group, a carboxylic acidgroup or a salt thereof, a sulfonic acid group or a salt thereof, aphosphoric acid group or a salt thereof, a C₁-C₂₀ alkyl group, a C₁-C₂₀alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, anaphthyl group, an azulenyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, a quinolinyl group, an isoquinolinyl group, a quinoxalinyl group,a quinazolinyl group, a carbazolyl group, and a triazinyl group, and L₁₆is selected from: a phenylene group, a naphthylene group, a fluorenylenegroup, a spiro-fluorenylene group, a benzofluorene group, adibenzofluorene group, a phenanthrenylene group, an anthracenylenegroup, a pyrenylene group, a chrysenylene group, a pyridinylene group, apyrazinylene group, a pyrimidinylene group, a pyridazinylene group, aquinolinylene group, an isoquinolinylene group, a quinoxalinylene group,a quinazolinylene group, a carbazolylene group, and a triazinylenegroup; and a phenylene group, a naphthylene group, a fluorenylene group,a spiro-fluorenylene group, a benzofluorenylene group, adibenzofluorenylene group, a phenanthrenylene group, an anthracenylenegroup, a pyrenylene group, a chrysenylene group, a pyridinylene group, apyrazinylene group, a pyrimidinylene group, a pyridazinylene group, aquinolinylene group, an isoquinolinylene group, a quinoxalinylene group,a quinazolinylene group, a carbazolylene group, and a triazinylenegroup, each substituted with at least one selected from deuterium, —F,—Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an aminogroup, an amidino group, a hydrazine group, a hydrazone group, acarboxylic acid group or a salt thereof, a sulfonic acid group or a saltthereof, a phosphoric acid group or a salt thereof, a C₁-C₂₀ alkylgroup, a C₁-C₂₀ alkoxy group, a phenyl group, a biphenyl group, aterphenyl group, a naphthyl group, a fluorenyl group, a spiro-fluorenylgroup, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthrenylgroup, an anthracenyl group, a pyrenyl group, a chrysenyl group, apyridinyl group, a pyrazinyl group, a pyrimidinyl group, a pyridazinylgroup, an isoindolyl group, a quinolinyl group, an isoquinolinyl group,a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, and atriazinyl group.
 11. The organic light-emitting device of claim 1,wherein a moiety represented by *-(L₁₄)_(b14)-(L₁₆)_(b16)-(L₁₅)_(b15)-*′in Formula 2 is represented by one selected from Formulae 3-1 to 3-7:

wherein, in Formulae 3-1 to 3-7, and *′ each indicate a binding site toa neighboring atom.
 12. The organic light-emitting device of claim 1,wherein R₁₁ to R₂₀ in Formula 2 are each independently selected from:hydrogen, deuterium, —F, —Cl, —Br, —I, a cyano group, a methyl group, anethyl group, an n-propyl group, an isopropyl group, an n-butyl group, anisobutyl group, a sec-butyl group, and a tert-butyl group; a methylgroup, an ethyl group, an n-propyl group, an isopropyl group, an n-butylgroup, an isobutyl group, a sec-butyl group, and a tert-butyl group,each substituted with at least one selected from deuterium, —F, —Cl,—Br, —I, and a cyano group; and a phenyl group, a naphthyl group, and apyridinyl group.
 13. The organic light-emitting device of claim 1,wherein the second compound is represented by Formula 2 Å or 2B:

wherein, in Formulae 2 Å and 2B, M₁₁, A₁₂, A₁₃, Y₁₁ to Y₁₄, T₁₁ to T₁₄,L₁₁ to L₁₆, b11 to b16, R₁₁ to R₁₄, and a11 to a14 are the same asdescribed in connection with Formula 2, Y₂₁ to Y₂₄ are eachindependently N or C, Y₃₁ to Y₃₄ are each independently N or C, and Y₄₁to Y₄₅ are each independently N or C.
 14. The organic light-emittingdevice of claim 1, wherein the second compound is selected fromCompounds BD1 to BD25, wherein Ph in Compounds BD1 to BD25 indicates aphenyl group:


15. The organic light-emitting device of claim 1, wherein the emissionlayer comprises a host and a dopant, the host comprises the firstcompound, and the dopant comprises the second compound.
 16. The organiclight-emitting device of claim 15, wherein the host further comprises aphosphine oxide-containing compound, and the phosphine oxide-containingcompound is different from the first compound.
 17. The organiclight-emitting device of claim 1, wherein the first electrode is ananode, the second electrode is a cathode, and the organic layer furthercomprises a hole transport region between the first electrode and theemission layer and an electron transport region between the emissionlayer and the second electrode, the hole transport region comprises atleast one selected from a hole injection layer, a hole transport layer,a buffer layer, an emission auxiliary layer, and an electron blockinglayer, and the electron transport region comprises at least one selectedfrom a hole blocking layer, an electron transport layer, and an electroninjection layer.
 18. The organic light-emitting device of claim 17,wherein the hole transport region comprises at least one of a holeinjection layer and a hole transport layer, and at least one of the holeinjection layer and the hole transport layer comprises a p-dopant, orthe hole transport region comprises a single film comprising a p-dopant.19. The organic light-emitting device of claim 17, wherein the electrontransport region comprises a hole blocking layer, and the hole blockinglayer comprises a phosphine oxide-containing compound or asilyl-containing compound.
 20. A flat-panel display apparatuscomprising: a thin film transistor comprising a source electrode, adrain electrode, and an active layer; and the organic light-emittingdevice of claim 1, wherein the first electrode of the organiclight-emitting device is electrically connected to one of the sourceelectrode and the drain electrode of the thin film transistor.